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What Is Cephalic Position?

The ideal fetal position for labor and delivery

• Why It's Best

Risks of Other Positions

• Determining Position
• Turning a Fetus

The cephalic position is when a fetus is head down when it is ready to enter the birth canal. This is one of a few variations of how a fetus can rest in the womb and is considered the ideal one for labor and delivery.

About 96% of babies are born in the cephalic position. Most settle into it between the 32nd and 36th weeks of pregnancy . Your healthcare provider will monitor the fetus's position during the last weeks of gestation to ensure this has happened by week 36.

If the fetus is not in the cephalic position at that point, the provider may try to turn it. If this doesn't work, some—but not all—practitioners will attempt to deliver vaginally, while others will recommend a Cesarean (C-section).

Getty Images

Why Is the Cephalic Position Best?

During labor, contractions dilate the cervix so the fetus has adequate room to come through the birth canal. The cephalic position is the easiest and safest way for the baby to pass through the birth canal.

If the fetus is in a noncephalic position, delivery becomes more challenging. Different fetal positions have a range of difficulties and varying risks.

A small percentage of babies present in noncephalic positions. This can pose risks both to the fetus and the mother, and make labor and delivery more challenging. It can also influence the way in which someone can deliver.

A fetus may actually find itself in any of these positions throughout pregnancy, as the move about the uterus. But as they grow, there will be less room to tumble around and they will settle into a final position.

It is at this point that noncephalic positions can pose significant risks.

Cephalic Posterior

A fetus may also present in an occiput or cephalic posterior position. This means they are positioned head down, but they are facing the abdomen instead of the back.

This position is also nicknamed "sunny-side up."

Presenting this way increases the chance of a painful and prolonged delivery.

There are three different types of breech fetal positioning:

• Frank breech: The legs are up with the feet near the head.
• Footling breech: One or both legs is lowered over the cervix.
• Complete breech: The fetus is bottom-first with knees bent.

A vaginal delivery is most times a safe way to deliver. But with breech positions, a vaginal delivery can be complicated.

When a baby is born in the breech position, the largest part—its head—is delivered last. This can result in them getting stuck in the birth canal (entrapped). This can cause injury or death.

The umbilical cord may also be damaged or slide down into the mouth of the womb, which can reduce or cut off the baby's oxygen supply.

Some providers are still comfortable performing a vaginal birth as long as the fetus is doing well. But breech is always a riskier delivery position compared with the cephalic position, and most cases require a C-section.

Likelihood of a Breech Baby

You are more likely to have a breech baby if you:

• Go into early labor before you're full term
• Have an abnormally shaped uterus, fibroids , or too much amniotic fluid
• Are pregnant with multiples
• Have placenta previa (when the placenta covers the cervix)

Transverse Lie

In transverse lie position, the fetus is presenting sideways across the uterus rather than vertically. They may be:

• Down, with the back facing the birth canal
• With one shoulder pointing toward the birth canal
• Up, with the hands and feet facing the birth canal

If a transverse lie is not corrected before labor, a C-section will be required. This is typically the case.

Determining Fetal Position

Your healthcare provider can determine if your baby is in cephalic presentation by performing a physical exam and ultrasound.

In the final weeks of pregnancy, your healthcare provider will feel your lower abdomen with their hands to assess the positioning of the baby. This includes where the head, back, and buttocks lie

If your healthcare provider senses that the fetus is in a breech position, they can use ultrasound to confirm their suspicion.

Turning a Fetus So They Are in Cephalic Position

External cephalic version (ECV) is a common, noninvasive procedure to turn a breech baby into cephalic position while it's still in the uterus.

This is only considered if a healthcare provider monitors presentation progress in the last trimester and notices that a fetus is maintaining a noncephalic position as your delivery date approaches.

External Cephalic Version (ECV)

ECV involves the healthcare provider applying pressure to your stomach to turn the fetus from the outside. They will attempt to rotate the head forward or backward and lift the buttocks in an upward position. Sometimes, they use ultrasound to help guide the process.

The best time to perform ECV is about 37 weeks of pregnancy. Afterward, the fetal heart rate will be monitored to make sure it’s within normal levels. You should be able to go home after having ECV done.

ECV has a 50% to 60% success rate. However, even if it does work, there is still a chance the fetus will return to the breech position before birth.

Natural Methods For Turning a Fetus

There are also natural methods that can help turn a fetus into cephalic position. There is no medical research that confirms their efficacy, however.

• Changing your position: Sometimes a fetus will move when you get into certain positions. Two specific movements that your provider may recommend include: Getting on your hands and knees and gently rocking back and forth. Another you could try is pushing your hips up in the air while laying on your back with your knees bent and feet flat on the floor (bridge pose).
• Playing stimulating sounds: Fetuses gravitate to sound. You may be successful at luring a fetus out of breech position by playing music or a recording of your voice near your lower abdomen.
• Chiropractic care: A chiropractor can try the Webster technique. This is a specific chiropractic analysis and adjustment which enables chiropractors to establish balance in the pregnant person's pelvis and reduce undue stress to the uterus and supporting ligaments.
• Acupuncture: This is a considerably safe way someone can try to turn a fetus. Some practitioners incorporate moxibustion—the burning of dried mugwort on certain areas of the body—because they believe it will enhance the chances of success.

A Word From Verywell

While most babies are born in cephalic position at delivery, this is not always the case. And while some fetuses can be turned, others may be more stubborn.

This may affect your labor and delivery wishes. Try to remember that having a healthy baby, and staying well yourself, are your ultimate priorities. That may mean diverting from your best laid plans.

Speaking to your healthcare provider about turning options and the safest route of delivery may help you adjust to this twist and feel better about how you will move ahead.

Glezerman M. Planned vaginal breech delivery: current status and the need to reconsider . Expert Rev Obstet Gynecol. 2012;7(2):159-166. doi:10.1586/eog.12.2

Cleveland Clinic. Fetal positions for birth .

MedlinePlus. Breech birth .

UT Southwestern Medical Center. Can you turn a breech baby around?

The American College of Obstetricians and Gynecologists. If your baby is breech .

Roecker CB. Breech repositioning unresponsive to Webster technique: coexistence of oligohydramnios .  Journal of Chiropractic Medicine . 2013;12(2):74-78. doi:10.1016/j.jcm.2013.06.003

By Cherie Berkley, MS Berkley is a journalist with a certification in global health from Johns Hopkins University and a master's degree in journalism.

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• Fetal presentation before birth

The way a baby is positioned in the uterus just before birth can have a big effect on labor and delivery. This positioning is called fetal presentation.

Babies twist, stretch and tumble quite a bit during pregnancy. Before labor starts, however, they usually come to rest in a way that allows them to be delivered through the birth canal headfirst. This position is called cephalic presentation. But there are other ways a baby may settle just before labor begins.

Following are some of the possible ways a baby may be positioned at the end of pregnancy.

Head down, face down

When a baby is head down, face down, the medical term for it is the cephalic occiput anterior position. This the most common position for a baby to be born in. With the face down and turned slightly to the side, the smallest part of the baby's head leads the way through the birth canal. It is the easiest way for a baby to be born.

Head down, face up

When a baby is head down, face up, the medical term for it is the cephalic occiput posterior position. In this position, it might be harder for a baby's head to go under the pubic bone during delivery. That can make labor take longer.

Most babies who begin labor in this position eventually turn to be face down. If that doesn't happen, and the second stage of labor is taking a long time, a member of the health care team may reach through the vagina to help the baby turn. This is called manual rotation.

In some cases, a baby can be born in the head-down, face-up position. Use of forceps or a vacuum device to help with delivery is more common when a baby is in this position than in the head-down, face-down position. In some cases, a C-section delivery may be needed.

Frank breech

When a baby's feet or buttocks are in place to come out first during birth, it's called a breech presentation. This happens in about 3% to 4% of babies close to the time of birth. The baby shown below is in a frank breech presentation. That's when the knees aren't bent, and the feet are close to the baby's head. This is the most common type of breech presentation.

If you are more than 36 weeks into your pregnancy and your baby is in a frank breech presentation, your health care professional may try to move the baby into a head-down position. This is done using a procedure called external cephalic version. It involves one or two members of the health care team putting pressure on your belly with their hands to get the baby to roll into a head-down position.

If the procedure isn't successful, or if the baby moves back into a breech position, talk with a member of your health care team about the choices you have for delivery. Most babies in a frank breech position are born by planned C-section.

Complete and incomplete breech

A complete breech presentation, as shown below, is when the baby has both knees bent and both legs pulled close to the body. In an incomplete breech, one or both of the legs are not pulled close to the body, and one or both of the feet or knees are below the baby's buttocks. If a baby is in either of these positions, you might feel kicking in the lower part of your belly.

If you are more than 36 weeks into your pregnancy and your baby is in a complete or incomplete breech presentation, your health care professional may try to move the baby into a head-down position. This is done using a procedure called external cephalic version. It involves one or two members of the health care team putting pressure on your belly with their hands to get the baby to roll into a head-down position.

If the procedure isn't successful, or if the baby moves back into a breech position, talk with a member of your health care team about the choices you have for delivery. Many babies in a complete or incomplete breech position are born by planned C-section.

When a baby is sideways — lying horizontal across the uterus, rather than vertical — it's called a transverse lie. In this position, the baby's back might be:

• Down, with the back facing the birth canal.
• Sideways, with one shoulder pointing toward the birth canal.
• Up, with the hands and feet facing the birth canal.

Although many babies are sideways early in pregnancy, few stay this way when labor begins.

If your baby is in a transverse lie during week 37 of your pregnancy, your health care professional may try to move the baby into a head-down position. This is done using a procedure called external cephalic version. External cephalic version involves one or two members of your health care team putting pressure on your belly with their hands to get the baby to roll into a head-down position.

If the procedure isn't successful, or if the baby moves back into a transverse lie, talk with a member of your health care team about the choices you have for delivery. Many babies who are in a transverse lie are born by C-section.

If you're pregnant with twins and only the twin that's lower in the uterus is head down, as shown below, your health care provider may first deliver that baby vaginally.

Then, in some cases, your health care team may suggest delivering the second twin in the breech position. Or they may try to move the second twin into a head-down position. This is done using a procedure called external cephalic version. External cephalic version involves one or two members of the health care team putting pressure on your belly with their hands to get the baby to roll into a head-down position.

Your health care team may suggest delivery by C-section for the second twin if:

• An attempt to deliver the baby in the breech position is not successful.
• You do not want to try to have the baby delivered vaginally in the breech position.
• An attempt to move the baby into a head-down position is not successful.
• You do not want to try to move the baby to a head-down position.

In some cases, your health care team may advise that you have both twins delivered by C-section. That might happen if the lower twin is not head down, the second twin has low or high birth weight as compared to the first twin, or if preterm labor starts.

• Landon MB, et al., eds. Normal labor and delivery. In: Gabbe's Obstetrics: Normal and Problem Pregnancies. 8th ed. Elsevier; 2021. https://www.clinicalkey.com. Accessed May 19, 2023.
• Holcroft Argani C, et al. Occiput posterior position. https://www.updtodate.com/contents/search. Accessed May 19, 2023.
• Frequently asked questions: If your baby is breech. American College of Obstetricians and Gynecologists https://www.acog.org/womens-health/faqs/if-your-baby-is-breech. Accessed May 22, 2023.
• Hofmeyr GJ. Overview of breech presentation. https://www.updtodate.com/contents/search. Accessed May 22, 2023.
• Strauss RA, et al. Transverse fetal lie. https://www.updtodate.com/contents/search. Accessed May 22, 2023.
• Chasen ST, et al. Twin pregnancy: Labor and delivery. https://www.updtodate.com/contents/search. Accessed May 22, 2023.
• Cohen R, et al. Is vaginal delivery of a breech second twin safe? A comparison between delivery of vertex and non-vertex second twins. The Journal of Maternal-Fetal & Neonatal Medicine. 2021; doi:10.1080/14767058.2021.2005569.
• Marnach ML (expert opinion). Mayo Clinic. May 31, 2023.

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Presentation and position of baby through pregnancy and at birth

9-minute read

If you are concerned about your baby’s movements, contact your doctor or midwife for advice immediately.

• If you baby is in a breech presentation, your doctor may recommend trying a technique called an external cephalic version to try and move your baby while they are still in the uterus for an easier birth.

What does presentation and position mean?

Presentation refers to the part of your baby’s body that is facing downwards in the direction of the birth canal.

Position refers to where your baby’s occiput (the bottom part of the back of their head) is in relation to your body.

If your baby is in a breech presentation , then position refers to where your baby’s sacrum (lower back) is in relation to your body.

People — including medical professionals — sometimes use these terms incorrectly. Sometimes when speaking about babies in breech presentation, the word ‘position’ will be used to refer to their presentation. For example, you may read information or hear people say ‘breech position’ instead of ‘breech presentation’.

What are the different types of presentation my baby could be in during pregnancy and birth?

Most babies present headfirst, also known as cephalic presentation. Most babies that are headfirst will be vertex presentation. This means that the crown of their head sits at the opening of your birth canal.

In rare cases, your baby can be headfirst but in face or brow presentation, which may not be suitable for vaginal birth.

If your baby is in a breech presentation, their feet or bottom will be closest to your birth canal. The 3 most common types of breech presentation are:

• frank or extended breech — where your baby’s legs are straight up in front of their body, with their feet up near their face
• complete or flexed breech — where your baby is in a sitting position with their legs crossed in front of their body and their feet near their bottom
• footling breech — where one or both of your baby’s feet are hanging below their bottom, so the foot or feet are coming first

Read more on breech presentation .

What are the different positions my baby could be in during pregnancy and birth?

If your baby is headfirst, the 3 main types of presentation are:

• anterior – when the back of your baby’s head is at the front of your belly
• lateral – when the back of your baby’s head is facing your side
• posterior – when the back of your baby’s head is towards your back

How will I know what presentation and position my baby is in?

Your doctor or midwife can usually work out your baby’s presentation by feeling your abdomen. They may also double check it with a portable ultrasound. Your baby’s presentation is usually checked around 36 weeks .

Your doctor or midwife will also confirm your baby’s head position in labour by examining your belly and using an ultrasound , and they may also do a vaginal examination . During the vaginal examination they are feeling for certain ridges on your baby’s head called sutures and fontanelles that help them work out which way your baby is positioned.

What is the ideal presentation and position for baby to be in for a vaginal birth?

For a vaginal birth, your baby will ideally be headfirst with the back of their head at the front of your belly, also known as being in the anterior position. This position is best for labour and birth since it means that the smallest part of your baby’s head goes down the birth canal first.

When does a baby usually get in the ideal presentation and position for birth?

Your baby will usually be in a headfirst position by 37 weeks of pregnancy. Around 3 in every 100 babies will be in breech presentation after 37 weeks.

Your baby’s position can change with your contractions during labour as they move down the birth canal, so their exact position can change during labour.

What are my options if baby isn't in the ideal presentation or position for a vaginal birth?

If your baby is in a breech presentation, your doctor may recommend a technique called an external cephalic version (ECV) to try and move your baby while they are still in the uterus . An ECV involves your doctor using their hands to apply pressure on your belly and help turn your baby to a headfirst position. It has a 1 in 2 chance of success and is a safe option in most pregnancies.

There is no evidence to show that alternative therapies, such as exercises, acupuncture or chiropractic treatments, help your baby change from a breech presentation to headfirst.

If your baby remains breech, your doctor may discuss having a breech vaginal birth. Not all doctors and hospitals offer this option. They may also suggest you birth your baby with a planned caesarean section .

If your baby’s presentation is headfirst but the position of your baby’s head is not ideal for labour, it can lead to a longer labour, and potential complications . The position of your baby’s head will often change as your labour progresses. If it doesn’t, sometimes you can still give birth without assistance, or you may need your doctor to help turn your baby’s head or help your birth with a vacuum or forceps .

Any procedure or decision for a type of birth will only go ahead with your consent . You will be able to discuss all the options with your doctor, and based on your preferences for yourself and your baby’s safety, make a decision together .

Resources and support

The Royal Australian and New Zealand College of Obstetrics and Gynaecology has a factsheet about the options available to you if your baby is in a breech presentation at the end of your pregnancy .

Mercy Perinatal has information on external cephalic version (ECV) safety and benefits if your baby is in a breech presentation at the end of your pregnancy.

The Women’s Hospital has information about the different presentations and positions your baby could be in, and how it can affect your birthing experience.

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Last reviewed: October 2023

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External cephalic version (ecv), malpresentation, breech pregnancy, search our site for.

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Fetal Presentation, Position, and Lie (Including Breech Presentation)

• Variations in Fetal Position and Presentation |

During pregnancy, the fetus can be positioned in many different ways inside the mother's uterus. The fetus may be head up or down or facing the mother's back or front. At first, the fetus can move around easily or shift position as the mother moves. Toward the end of the pregnancy the fetus is larger, has less room to move, and stays in one position. How the fetus is positioned has an important effect on delivery and, for certain positions, a cesarean delivery is necessary. There are medical terms that describe precisely how the fetus is positioned, and identifying the fetal position helps doctors to anticipate potential difficulties during labor and delivery.

Presentation refers to the part of the fetus’s body that leads the way out through the birth canal (called the presenting part). Usually, the head leads the way, but sometimes the buttocks (breech presentation), shoulder, or face leads the way.

Position refers to whether the fetus is facing backward (occiput anterior) or forward (occiput posterior). The occiput is a bone at the back of the baby's head. Therefore, facing backward is called occiput anterior (facing the mother’s back and facing down when the mother lies on her back). Facing forward is called occiput posterior (facing toward the mother's pubic bone and facing up when the mother lies on her back).

Lie refers to the angle of the fetus in relation to the mother and the uterus. Up-and-down (with the baby's spine parallel to mother's spine, called longitudinal) is normal, but sometimes the lie is sideways (transverse) or at an angle (oblique).

For these aspects of fetal positioning, the combination that is the most common, safest, and easiest for the mother to deliver is the following:

Head first (called vertex or cephalic presentation)

Facing backward (occiput anterior position)

Spine parallel to mother's spine (longitudinal lie)

Neck bent forward with chin tucked

Arms folded across the chest

If the fetus is in a different position, lie, or presentation, labor may be more difficult, and a normal vaginal delivery may not be possible.

Variations in fetal presentation, position, or lie may occur when

The fetus is too large for the mother's pelvis (fetopelvic disproportion).

The uterus is abnormally shaped or contains growths such as fibroids .

The fetus has a birth defect .

There is more than one fetus (multiple gestation).

Position and Presentation of the Fetus

Variations in Fetal Position and Presentation

Some variations in position and presentation that make delivery difficult occur frequently.

Occiput posterior position

In occiput posterior position (sometimes called sunny-side up), the fetus is head first (vertex presentation) but is facing forward (toward the mother's pubic bone—that is, facing up when the mother lies on her back). This is a very common position that is not abnormal, but it makes delivery more difficult than when the fetus is in the occiput anterior position (facing toward the mother's spine—that is facing down when the mother lies on her back).

When a fetus faces up, the neck is often straightened rather than bent,which requires more room for the head to pass through the birth canal. Delivery assisted by a vacuum device or forceps or cesarean delivery may be necessary.

Breech presentation

In breech presentation, the baby's buttocks or sometimes the feet are positioned to deliver first (before the head).

When delivered vaginally, babies that present buttocks first are more at risk of injury or even death than those that present head first.

The reason for the risks to babies in breech presentation is that the baby's hips and buttocks are not as wide as the head. Therefore, when the hips and buttocks pass through the cervix first, the passageway may not be wide enough for the head to pass through. In addition, when the head follows the buttocks, the neck may be bent slightly backwards. The neck being bent backward increases the width required for delivery as compared to when the head is angled forward with the chin tucked, which is the position that is easiest for delivery. Thus, the baby’s body may be delivered and then the head may get caught and not be able to pass through the birth canal. When the baby’s head is caught, this puts pressure on the umbilical cord in the birth canal, so that very little oxygen can reach the baby. Brain damage due to lack of oxygen is more common among breech babies than among those presenting head first.

In a first delivery, these problems may occur more frequently because a woman’s tissues have not been stretched by previous deliveries. Because of risk of injury or even death to the baby, cesarean delivery is preferred when the fetus is in breech presentation, unless the doctor is very experienced with and skilled at delivering breech babies or there is not an adequate facility or equipment to safely perform a cesarean delivery.

Breech presentation is more likely to occur in the following circumstances:

Labor starts too soon (preterm labor).

The uterus is abnormally shaped or contains abnormal growths such as fibroids .

Other presentations

In face presentation, the baby's neck arches back so that the face presents first rather than the top of the head.

In brow presentation, the neck is moderately arched so that the brow presents first.

Usually, fetuses do not stay in a face or brow presentation. These presentations often change to a vertex (top of the head) presentation before or during labor. If they do not, a cesarean delivery is usually recommended.

In transverse lie, the fetus lies horizontally across the birth canal and presents shoulder first. A cesarean delivery is done, unless the fetus is the second in a set of twins. In such a case, the fetus may be turned to be delivered through the vagina.

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Management of Labour and Delivery – Questions

Rekha Wuntakal, Madhavi Kalidindi, Tony Hollingworth in Get Through , 2014

For each clinical scenario below, choose the single most appropriate stage of labour from the above list of options. Each option may be used once, more than once or not at all. A 30-year-old para 3 woman was admitted at term with regular uterine activity at 5 cm cervical dilatation and 4 hours later she delivered a female neonate with APGARs 9, 10, 10 at 1, 5 and 10 minutes. Syntometrine injection was given immediately after delivery and placenta with membranes was delivered completely 20 minutes after the delivery of the baby by continuous cord traction.A 23-year-old para 3 woman was admitted after spontaneous rupture of membranes at 39 weeks’ gestation. She is contracting 4 in 10 minutes and pushing involuntarily. On vaginal examination the cervix was fully dilated, vertex was 2 cm below the spines in direct occipito-anterior position with minimal caput and moulding.A 30-year-old nulliparous woman was admitted at term with uterine contractions once in every 5 minutes. On examination, the fetus is in cephalic presentation with two fifths palpable per abdomen. The cervix is central, soft, fully effaced and 2 cm dilated with intact membranes.

Biometric Measurements and Normal Growth Parameters in a Child

Nirmal Raj Gopinathan in Clinical Orthopedic Examination of a Child , 2021

In cephalic presentation, the intra-uterine fetal position is of universal flexion, which is carried by the child to the immediate post-partum period. The hips and knees are flexed. The lower legs are internally rotated. The feet are further internally rotated with respect to the lower legs. At times there is an external rotational contracture of the hip that tends to mask the true femoral rotational profile. The anatomy of the lower limbs changes significantly as the child grows. This is primarily in response to the development of motor abilities and the ability of the child to crawl, cruise, stand, walk, and finally run. These changes are seen right from the hip joints, the femoral neck, knees, and tibia to the feet.

DRCOG MCQs for Circuit A Questions

Una F. Coales in DRCOG: Practice MCQs and OSCEs: How to Pass First Time three Complete MCQ Practice Exams (180 MCQs) Three Complete OSCE Practice Papers (60 Questions) Detailed Answers and Tips , 2020

External cephalic version: Used to convert a breech presentation to cephalic presentation.Not contraindicated if there is a prior Caesarean section scar.Can cause premature labour.Contraindicated in hypertension.Can be performed after 33 weeks' gestation in a rhesus-negative mother.

Complex maternal congenital anomalies – a rare presentation and delivery through a supra-umbilical abdominal incision

Published in Journal of Obstetrics and Gynaecology , 2018

Samantha Bonner, Yara Mohammed

She had a spontaneous conception and booked at 9 weeks of gestation under consultant-led care. A scan confirmed the pregnancy was in the right uterus. She had no other significant medical history but did suffer from recurrent urinary tract infections and hence was on low-dose antibiotic prophylaxis. There was no sonographic evidence of hydronephrosis. Her body mass index (BMI) was 18 at the time of booking. Combined screening was low risk and she had a normal 20 week anomaly scan. She had serial growth scans which demonstrated a normal growth trajectory on a customised chart. The baby was consistently a cephalic presentation. She had multidisciplinary antenatal care, including specialist urologists, general surgeons, obstetricians and anaesthetists. An antenatal MRI scan had shown extensive adhesions over the lower segment of the uterus. She was extensively counselled regarding the mode of delivery and this was scheduled at 37 weeks of gestation to avoid the potential of spontaneous labour and an emergency Caesarean section.

Utilization of epidural volume extension technique for external cephalic version

Published in Baylor University Medical Center Proceedings , 2021

Hanna Hussey, James Damron, Mark F. Powell, Michelle Tubinis

Repeat ultrasound demonstrated breech presentation, normal amniotic fluid volume, and fetal head toward the maternal left abdomen. After 0.25 mg of intramuscular terbutaline injection, a forward roll was initiated by applying pressure from behind the fetal head toward the maternal left. Continuous progress was made and bedside ultrasound showed cephalic presentation. Immediately after successful ECV, the fetal heart rate was 70 beats/min but returned to baseline with conservative measures. Motor blockade regressed after approximately 1.5 hours. After 4 hours of fetal heart rate monitoring and tocometry, the patient was deemed stable for discharge. Follow-up discussion with the patient via phone call on postprocedure day 1 confirmed that she was not experiencing pain or concerning symptoms for neuraxial complications. She returned to the labor and delivery unit at 40 weeks’ gestation for elective induction of labor and had a successful vaginal delivery.

Antenatal scoring system in predicting the success of planned vaginal birth following one previous caesarean section

Aida Kalok, Shahril A. Zabil, Muhammad Abdul Jamil, Pei Shan Lim, Mohamad Nasir Shafiee, Nirmala Kampan, Shamsul Azhar Shah, Nor Azlin Mohamed Ismail

The inclusion criteria were pregnant women at 36 weeks of gestation or more with singleton foetus in cephalic presentation, who agreed for trial of vaginal delivery after one lower segment caesarean section. We excluded women with contraindication for vaginal birth, or who declined trial of vaginal delivery from this study. Previous antenatal history was noted and recorded during the 36-week assessment, including year and indication for previous caesarean section. Recurrent indications involved were cephalopelvic disproportion and obstructed labour. While non-recurrent indications were foetal distress and malpresentation. Past operative notes were checked for any operative complications such as extended uterine tear, organ injury and post-partum haemorrhage. Information regarding current pregnancy including pre-existing medical disorder was recorded. Estimated foetal weight based on ultrasound scan at 36 weeks of gestation was used in this study.

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Why Is Cephalic Presentation Ideal For Childbirth?

5   Dec   2017 | 8 min Read

During labour, contractions stretch your birth canal so that your baby has adequate room to come through during birth. The cephalic presentation is the safest and easiest way for your baby to pass through the birth canal.

If your baby is in a non-cephalic position, delivery can become more challenging. Different fetal positions pose a range of difficulties and varying risks and may not be considered ideal birthing positions.

Two Kinds of Cephalic Positions

There are two kinds of cephalic positions:

• Cephalic occiput anterior , where your baby’s head is down and is facing toward your back.
• Cephalic occiput posterior , where your baby is positioned head down, but they are facing your abdomen instead of your back. This position is also nicknamed ‘sunny-side-up’ and can increase the chances of prolonged and painful delivery. 

How to Know if Your Baby is In a Cephalic Position?

You can feel your baby’s position by rubbing your hand on your belly. If you feel your little one’s stomach in the upper stomach, then your baby is in a cephalic position. But if you feel their kicks in the lower stomach, then it could mean that your baby is in a breech position.

You can also determine whether your baby is in the anterior or posterior cephalic position. If your baby is in the anterior position, you may feel their movement underneath your ribs and your belly button could also pop out. If your baby is in the posterior position, then you may feel their kicks in their abdomen, and your stomach may appear rounded up instead of flat. 

You can also determine your baby’s position through an ultrasound scan or a physical examination at your healthcare provider’s office. 

Benefits of Cephalic Presentation in Pregnancy

Cephalic presentation is one of the most ideal birth positions, and has the following benefits:

• It is the safest way to give birth as your baby’s position is head-down and prevents the risk of any injuries.
• It can help your baby move through the delivery canal as safely and easily as possible.
• It increases the chances of smooth labour and delivery.

Are There Any Risks Involved in Cephalic Position?

Conditions like a cephalic posterior position in addition to a narrow pelvis of the mother can increase the risk of pregnancy complications during delivery. Some babies in the head-first cephalic presentation might have their heads tilted backward. This may, in some rare cases, cause preterm delivery.

What are the Risks Associated with Other Birth Positions?

A small percentage of babies may settle into a non-cephalic position before their birth. This can pose risks to both your and your baby’s health, and also influence the way in which you deliver. 

In the next section, we have discussed a few positions that your baby can settle in throughout pregnancy, as they move around the uterus. But as they grow old, there will be less space for them to tumble around, and they will settle into their final position. This is when non-cephalic positions can pose a risk.  

Breech Position

There are three types of breech fetal positioning:

• Frank breech : Your baby’s legs stick straight up along with their feet near their head.
• Footling breech: One or both of your baby’s legs are lowered over your cervix.
• Complete breech: Your baby is positioned bottom-first with their knees bent.

If your baby is in a breech position , vaginal delivery is considered complicated. When a baby is born in breech position, the largest part of their body, that is, their head is delivered last. This can lead to injury or even fetal distress. Moreover, the umbilical cord may also get damaged or get wrapped around your baby’s neck, cutting off their oxygen supply.  

If your baby is in a breech position, your healthcare provider may recommend a c-section, or they may try ways to flip your baby’s position in a cephalic presentation.

Transverse Lie

In this position, your baby settles in sideways across the uterus rather than being in a vertical position. They may be:

• Head-down, with their back facing the birth canal
• One shoulder pointing toward the birth canal
• Up with their hands and feet facing the birth canal

If your baby settles in this position, then your healthcare provider may suggest a c-section to reduce the risk of distress in your baby and other pregnancy complications.

Turning Your Baby Into A Cephalic Position

External cephalic version (ECV) is a common, and non-invasive procedure that helps turn your baby into a cephalic position while they are in the womb. However, your healthcare provider may only consider this procedure if they consider you have a stable health condition in the last trimester, and if your baby hasn’t changed their position by the 36th week.

You can also try some natural remedies to change your baby’s position, such as:

• Lying in a bridge position: Movements like bridge position can sometimes help move your baby into a more suitable position. Lie on your back with your feet flat on the ground and your legs bent. Raise your pelvis and hips into a bridge position and hold for 5-10 minutes. Repeat several times daily.
• Chiropractic care: A chiropractor can help with the adjustment of your baby’s position and also reduce stress in them.
• Acupuncture: After your doctor’s go-ahead, you can also consider acupuncture to get your baby to settle into an ideal birthing position.

While most babies settle in a cephalic presentation by the 36th week of pregnancy, some may lie in a breech or transverse position before birth. Since the cephalic position is considered the safest, your doctor may recommend certain procedures to flip your baby’s position to make your labour and delivery smooth. You may also try the natural methods that we discussed above to get your baby into a safe birthing position and prevent risks or other pregnancy complications. 

When Should A Baby Be In A Cephalic Position?

Your baby would likely naturally drop into a cephalic position between weeks 37 to 40 of your pregnancy .

Is Cephalic Position Safe?

Research shows that 95% of babies take the cephalic position a few weeks or days before their due date. It is considered to be the safest position. It ensures a smooth birthing process.

While most of the babies are in cephalic position at delivery, this is not always the case. If you have a breech baby, you can discuss the available options for delivery with your doctor.

Does cephalic presentation mean labour is near?

Head-down is the ideal position for your baby within your uterus during birth. This is known as the cephalic position. This posture allows your baby to pass through the delivery canal more easily and safely.

Can babies change from cephalic to breech?

The external cephalic version (ECV) is the most frequent procedure used for turning a breech infant.

How can I keep my baby in a cephalic position?

While your baby naturally gets into this position, you can try some exercises to ensure that they settle in cephalic presentation. Exercises such as breech tilt, forward-leaning position (spinning babies program), cat and camel pose can help.

Stitches after a normal delivery : How many stitches do you need after a vaginal delivery? Tap this post to know.

Vaginal birth after caesarean delivery : Learn all about the precautions to consider before having a vaginal delivery after a c-section procedure. 

How many c-sections can you have : Tap this post to know the total number of c-sections that you can safely have.

Cover Image Credit: Freepik.com

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You and your baby at 32 weeks pregnant

Your baby at 32 weeks.

By about 32 weeks, the baby is usually lying with their head pointing downwards, ready for birth. This is known as cephalic presentation.

If your baby is not lying head down at this stage, it's not a cause for concern – there's still time for them to turn.

The amount of amniotic fluid in your uterus is increasing, and your baby is still swallowing fluid and passing it out as urine.

You at 32 weeks

Being active and fit during pregnancy will help you adapt to your changing shape and weight gain. It can also help you cope with labour and get back into shape after the birth.

Find out about exercise in pregnancy .

You may develop pelvic pain in pregnancy. This is not harmful to your baby, but it can cause severe pain and make it difficult for you to get around.

Find out about ways to tackle pelvic pain in pregnancy .

Read about the benefits of breastfeeding for you and your baby. It's never too early to start thinking about how you're going to feed your baby, and you do not have to make up your mind until your baby is born.

Things to think about

• how you might feel after the birth

Start4Life has more about you and your baby at 32 weeks pregnant .

You can sign up for Start4Life's weekly emails for expert advice, videos and tips on pregnancy, birth and beyond.

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Pelvimetry for fetal cephalic presentations at or near term for deciding on mode of delivery

Pelvimetry assesses the size of a woman's pelvis aiming to predict whether she will be able to give birth vaginally or not. This can be done by clinical examination, or by conventional X‐rays, computerised tomography (CT) scanning, or magnetic resonance imaging (MRI).

To assess the effects of pelvimetry (performed antenatally or intrapartum) on the method of birth, on perinatal mortality and morbidity, and on maternal morbidity. This review concentrates exclusively on women whose fetuses have a cephalic presentation.

Search methods

We searched Cochrane Pregnancy and Childbirth Group's Trials Register (31 January 2017) and reference lists of retrieved studies.

Selection criteria

Randomised controlled trials (including quasi‐randomised) assessing the use of pelvimetry versus no pelvimetry or assessing different types of pelvimetry in women with a cephalic presentation at or near term were included. Cluster trials were eligible for inclusion, but none were identified.

Data collection and analysis

Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. We assessed the quality of the evidence using the GRADE approach.

Main results

Five trials with a total of 1159 women were included. All used X‐ray pelvimetry to assess the pelvis. X‐ray pelvimetry versus no pelvimetry or clinical pelvimetry is the only comparison included in this review due to the lack of trials identified that examined other types of radiological pelvimetry or that compared clinical pelvimetry versus no pelvimetry.

The included trials were generally at high risk of bias. There is an overall high risk of performance bias due to lack of blinding of women and staff. Two studies were also at high risk of selection bias. We used GRADEpro software to grade evidence for our selected outcomes; for caesarean section we rated the evidence low quality and all the other outcomes (perinatal mortality, wound sepsis, blood transfusion, scar dehiscence and admission to special care baby unit) as very low quality. Downgrading was due to risk of bias relating to lack of allocation concealment and blinding, and imprecision of effect estimates.

Women undergoing X‐ray pelvimetry were more likely to have a caesarean section (risk ratio (RR) 1.34, 95% confidence interval (CI) 1.19 to 1.52; 1159 women; 5 studies; low‐quality evidence ). There were no clear differences between groups for perinatal outcomes: perinatal mortality (RR 0.53, 95% CI 0.19 to 1.45; 1159 infants; 5 studies; very low‐quality evidence ), perinatal asphyxia (RR 0.66, 95% CI 0.39 to 1.10; 305 infants; 1 study), and admission to special care baby unit (RR 0.20, 95% CI 0.01 to 4.13; 288 infants; 1 study; very low‐quality evidence ). Other outcomes assessed were wound sepsis (RR 0.83, 95% CI 0.26 to 2.67; 288 women; 1 study; very low‐quality evidence ), blood transfusion (RR 1.00, 95% CI 0.39 to 2.59; 288 women; 1 study; very low‐quality evidence ), and scar dehiscence (RR 0.59, 95% CI 0.14 to 2.46; 390 women; 2 studies; very low‐quality evidence ). Again, no clear differences were found for these outcomes between the women who received X‐ray pelvimetry and those who did not. Apgar score less than seven at five minutes was not reported in any study.

Authors' conclusions

X‐ray pelvimetry versus no pelvimetry or clinical pelvimetry is the only comparison included in this review due to the lack of trials identified that used other types or pelvimetry (other radiological examination or clinical pelvimetry versus no pelvimetry). There is not enough evidence to support the use of X‐ray pelvimetry for deciding on mode of delivery in women whose fetuses have a cephalic presentation. Women who undergo an X‐ray pelvimetry may be more likely to have a caesarean section.

Further research should be directed towards defining whether there are specific clinical situations in which pelvimetry can be shown to be of value. Newer methods of pelvimetry (CT, MRI) should be subjected to randomised trials to assess their value. Further trials of X‐ray pelvimetry in cephalic presentations would be of value if large enough to assess the effect on perinatal mortality.

Plain language summary

What is the issue?

Does the use of pelvimetry to assess the size of the woman's pelvis improve outcomes for baby and mother? Pelvimetry might identify babies whose heads are too big for their mother's pelvis. In this case, an elective caesarean section might improve the outcome. Forms of pelvimetry include radiological pelvimetry (X‐ray, computerised tomography (CT) scan or magnetic resonance imaging (MRI)) and clinical examination of the woman. We planned to include all studies comparing the use of clinical or radiological (X‐ray, CT or MRI) pelvimetry versus no pelvimetry, or different types of pelvimetry.

Why is this important?

Sometimes, normal labour does not progress because the baby's head is too big, or the pelvis of the mother is too small, for the baby to pass through. This is called "cephalo‐pelvic disproportion" or "obstructed labour" which may lead to an emergency caesarean section with possible risks for both mother and baby. A pregnant mother or her caregiver might be worried that disproportion could occur and for this reason, pelvimetry can be performed either before or during labour. It can be undertaken by clinical examination, X‐ray, CT‐scan or MRI. Pelvimetry measures the diameters of the pelvis and the baby's head. However, doing a pelvimetry also has implications: clinical examination might be very uncomfortable for the mother, X‐ray and CT‐scanning might be harmful for the baby and MRI is very expensive. All of these techniques have to be performed meticulously by experienced and skilled people to have any real value.

If we could diagnose the disproportion accurately before birth using pelvimetry, we might reduce the need for an emergency caesarean section and plan an elective procedure, with better outcomes for the baby and less complications for the mother.

What evidence did we find?

We searched for evidence on 30th November 2016 and identified five trials with a total of 1159 pregnant women. All five trials used X‐ray pelvimetry in comparison to no X‐ray pelvimetry.

The women who received X‐ray pelvimetry were more likely to have a caesarean section ( low‐quality evidence ). Whether a woman had pelvimetry or not, we found no difference in the numbers of babies that died ( very low‐quality evidence ), who did not have enough oxygen during labour, or were admitted to special care baby units ( very low‐quality evidence ). For the women, no differences were found between numbers of women with wound sepsis, those who received a blood transfusion, or those whose caesarean section scar began to break down ( all very low‐quality evidence ). Apgar score less than seven at five minutes was not reported in any study.

What does this mean?

There is too little evidence (the majority of which is low quality) to show whether measuring the size of the woman's pelvis (pelvimetry) is beneficial and safe when the baby is in a head‐down position. The number of women having a caesarean section increased if women had X‐ray pelvimetry but there was insufficient good‐quality evidence to show if pelvimetry improves outcomes for the baby. More research is needed.

Summary of findings

Description of the condition.

Cephalo‐pelvic disproportion (CPD) is one of the leading indications for an emergency caesarean section. CPD occurs when there is a mismatch between the fetal head and the maternal pelvis (when the fetal head is too big for the pelvis), resulting in obstructed labour.

Emergency caesarean sections have been shown to have an increased risk of maternal and neonatal morbidity and mortality ( van Ham 1997 ). Women undergoing an emergency caesarean section are at an increased risk for intra‐ and postoperative complications such as haemorrhage (tearing of the uterine incision into the parametrium or cervix, hysterotomy extension), infection (wound sepsis, endometritis), deep vein thrombosis and prolonged hospitalisation. Risks for the neonate include respiratory problems and trauma.

Women with a previous caesarean scar are known to be at risk for uterine rupture, stillbirth and placenta praevia in subsequent pregnancies. Performing a repeat caesarean section also increases the risk of bowel or bladder injury and haemorrhage and women who have had a previous caesarean section can be offered a trial of labour (vaginal birth after caesarean section (VBAC)) to reduce the intra‐ and postoperative complications of a caesarean section. However, the low but life‐threatening risk (for both mother and fetus) of a uterine rupture during labour has to be taken into consideration and explained to the woman ( Dodd 2013 ).

Description of the intervention

Assessment of the size of a woman's pelvis (pelvimetry) can be achieved by clinical examination (where the bony pelvis is digitally examined to identify prominent structures that may cause obstructed labour), or by conventional X‐rays (usually a lateral and anterior‐posterior view used to physically measure the sizes of the pelvic inlet, midpelvis and pelvic outlet, Morgan 1992 ), computerised tomography (CT) scanning (measuring the pelvis in the lateral, anterior‐posterior and axial views, Morris 1993 ), or magnetic resonance imaging (MRI, measuring of a midline sagittal, and oblique coronal views of the pelvis, Sporri 2002 ).

How the intervention might work

The aim of pelvimetry (whichever method is used) in women whose fetuses have a cephalic presentation, is to detect the presence of cephalo‐pelvic disproportion and therefore the need for caesarean section. Pelvimetry may influence clinical care since clinicians who feel that vaginal birth would be impossible, would offer the woman an elective caesarean section, thereby reducing the need of an emergency caesarean section. The criteria for determining an adequate or small pelvis have been from descriptive studies and senior opinions ( Mengert 1948 ).

Why it is important to do this review

These techniques are not without risks, the greatest of all being a false positive result and unnecessary caesarean section. Clinical pelvimetry is very uncomfortable for the woman, X‐rays and CT scanning expose the fetus to radiation (the latter slightly less so), and MRI is very expensive. All of these techniques have to be performed meticulously by experienced and skilled people in order to have any value at all.

To assess the effects of pelvimetry (performed antenatally, or intrapartum) on the method of birth, on perinatal mortality and morbidity, and on maternal morbidity. This review concentrates exclusively on women whose fetuses have a cephalic presentation.

Criteria for considering studies for this review

Types of studies

We included all randomised controlled trials (including quasi‐randomised) comparing pelvimetry in cephalic presentations versus no pelvimetry or comparing different types of pelvimetry. We would have included cluster trials if they had been identified during the search. Cross‐over studies were not eligible for this review.

If an abstract was of interest, we would have contacted the authors for further information about their trial.

Types of participants

Pregnant women with a singleton, cephalic presentation fetus who have or have not had a previous caesarean section. Studies that recruited women before, or during labour were included as well as women for spontaneous labour, induction of labour, or trial of scar after previous caesarean section (otherwise known as vaginal birth after caesarean or VBAC).

Types of interventions

The main intervention of interest is pelvimetry as a predictor of cephalo‐pelvic disproportion. Control groups could include women who did not have pelvimetry or who had different types of pelvimetry.

We planned to include studies comparing different methods of clinical or radiological pelvimetry such as X‐rays, computerised tomography (CT) scanning or magnetic resonance imaging (MRI). We reported women who have had one previous caesarean section and women who have had no previous section, or are nulliparous, in separate clinical subgroups.

Types of outcome measures

Primary outcomes, caesarean section, perinatal mortality, secondary outcomes, maternal outcomes, puerperal pyrexia, wound sepsis, blood transfusion, scar dehiscence, perinatal outcomes, perinatal asphyxia.

• Admission to special care baby units

Apgar score less than seven at five minutes

Search methods for identification of studies.

The following methods section of this review is based on a standard template used by Cochrane Pregnancy and Childbirth.

Electronic searches

We searched Cochrane Pregnancy and Childbirth’s Trials Register by contacting their Information Specialist (31 January 2017).

The Register is a database containing over 22,000 reports of controlled trials in the field of pregnancy and childbirth. For full search methods used to populate Pregnancy and Childbirth’s Trials Register including the detailed search strategies for CENTRAL, MEDLINE, Embase and CINAHL; the list of handsearched journals and conference proceedings, and the list of journals reviewed via the current awareness service, please follow this link to the editorial information about the Cochrane Pregnancy and Childbirth in the Cochrane Library and select the ‘ Specialized Register ’ section from the options on the left side of the screen.

Briefly, Cochrane Pregnancy and Childbirth’s Trials Register is maintained by their Information Specialist and contains trials identified from:

• monthly searches of the Cochrane Central Register of Controlled Trials (CENTRAL);
• weekly searches of MEDLINE (Ovid);
• weekly searches of Embase (Ovid);
• monthly searches of CINAHL (EBSCO);
• handsearches of 30 journals and the proceedings of major conferences;
• weekly current awareness alerts for a further 44 journals plus monthly BioMed Central email alerts.

Search results are screened by two people and the full text of all relevant trial reports identified through the searching activities described above is reviewed. Based on the intervention described, each trial report is assigned a number that corresponds to a specific Pregnancy and Childbirth review topic (or topics), and is then added to the Register. The Information Specialist searches the Register for each review using this topic number rather than keywords. This results in a more specific search set which has been fully accounted for in the relevant review sections ( Included studies ; Excluded studies ).

Searching other resources

We searched the reference lists of retrieved studies.

We did not apply any language or date restrictions.

For methods used in the previous version of this review, see Pattinson 1997 .

For this update, the following methods were used for assessing the two reports that were identified as a result of the updated search.

The following methods section of this review is based on a standard template used by Cochrane Pregnancy and Childbirth Group.

Selection of studies

Two review authors independently assessed for inclusion all the potential studies identified as a result of the search strategy. We resolved any disagreement through discussion or, if required, we consulted the third review author.

Data extraction and management

We designed a form to extract data. For eligible studies, two review authors extracted the data using the agreed form. We resolved discrepancies through discussion or, if required, we consulted the third review author. Data were entered into Review Manager software ( RevMan 2014 ) and checked for accuracy.

When information regarding any of the above was unclear, we planned to contact authors of the original reports to provide further details.

Assessment of risk of bias in included studies

Two review authors independently assessed risk of bias for each study using the criteria outlined in the Cochrane Handbook for Systematic Reviews of Interventions ( Higgins 2011 ). Any disagreement was resolved by discussion or by involving a third assessor.

(1) Random sequence generation (checking for possible selection bias)

We described for each included study the method used to generate the allocation sequence in sufficient detail to allow an assessment of whether it should produce comparable groups.

We assessed the method as:

• low risk of bias (any truly random process, e.g. random number table; computer random number generator);
• high risk of bias (any non‐random process, e.g. odd or even date of birth; hospital or clinic record number);
• unclear risk of bias.

(2) Allocation concealment (checking for possible selection bias)

We described for each included study the method used to conceal allocation to interventions prior to assignment and assessed whether intervention allocation could have been foreseen in advance of, or during recruitment, or changed after assignment.

We assessed the methods as:

• low risk of bias (e.g. telephone or central randomisation; consecutively numbered sealed opaque envelopes);
• high risk of bias (open random allocation; unsealed or non‐opaque envelopes, alternation; date of birth);

(3.1) Blinding of participants and personnel (checking for possible performance bias)

We described for each included study the methods used, if any, to blind study participants and personnel from knowledge of which intervention a participant received. We considered that studies were at low risk of bias if they were blinded, or if we judged that the lack of blinding unlikely to affect results. We assessed blinding separately for different outcomes or classes of outcomes.

• low, high or unclear risk of bias for participants;
• low, high or unclear risk of bias for personnel.

(3.2) Blinding of outcome assessment (checking for possible detection bias)

We described for each included study the methods used, if any, to blind outcome assessors from knowledge of which intervention a participant received. We assessed blinding separately for different outcomes or classes of outcomes.

We assessed methods used to blind outcome assessment as:

• low, high or unclear risk of bias.

(4) Incomplete outcome data (checking for possible attrition bias due to the amount, nature and handling of incomplete outcome data)

We described for each included study, and for each outcome or class of outcomes, the completeness of data including attrition and exclusions from the analysis. We stated whether attrition and exclusions were reported and the numbers included in the analysis at each stage (compared with the total randomised participants), reasons for attrition or exclusion where reported, and whether missing data were balanced across groups or were related to outcomes. Where sufficient information was reported, or could be supplied by the trial authors, we planned to re‐include missing data in the analyses which we undertook.

We assessed methods as:

• low risk of bias (e.g. no missing outcome data; missing outcome data balanced across groups);
• high risk of bias (e.g. numbers or reasons for missing data imbalanced across groups; ‘as treated’ analysis done with substantial departure of intervention received from that assigned at randomisation);

(5) Selective reporting (checking for reporting bias)

We described for each included study how we investigated the possibility of selective outcome reporting bias and what we found.

• low risk of bias (where it is clear that all of the study’s pre‐specified outcomes and all expected outcomes of interest to the review have been reported);
• high risk of bias (where not all the study’s pre‐specified outcomes have been reported; one or more reported primary outcomes were not pre‐specified; outcomes of interest are reported incompletely and so cannot be used; study fails to include results of a key outcome that would have been expected to have been reported);

(6) Other bias (checking for bias due to problems not covered by (1) to (5) above)

We described for each included study any important concerns we had about other possible sources of bias.

(7) Overall risk of bias

We made explicit judgements about whether studies were at high risk of bias, according to the criteria given in the Handbook ( Higgins 2011 ). With reference to (1) to (6) above, we planned to assess the likely magnitude and direction of the bias and whether we considered it is likely to impact on the findings. In future updates, we will explore the impact of the level of bias through undertaking sensitivity analyses ‐ see Sensitivity analysis .

Assessment of the quality of the evidence using the GRADE approach

For this update the quality of the evidence was assessed using the GRADE approach as outlined in the GRADE handbook in order to assess the quality of the body of evidence relating to the following outcomes for the main comparison ‐ X‐ray pelvimetry versus no pelvimetry or clinical pelvimetry in cephalic presentations.

We used the GRADEpro Guideline Development Tool to import data from Review Manager 5.3 ( RevMan 2014 ) in order to create a 'Summary of findings’ table. A summary of the intervention effect and a measure of quality for each of the above outcomes was produced using the GRADE approach. The GRADE approach uses five considerations (study limitations, consistency of effect, imprecision, indirectness and publication bias) to assess the quality of the body of evidence for each outcome. The evidence can be downgraded from 'high quality' by one level for serious (or by two levels for very serious) limitations, depending on assessments for risk of bias, indirectness of evidence, serious inconsistency, imprecision of effect estimates or potential publication bias.

Measures of treatment effect

Dichotomous data.

For dichotomous data, we presented results as summary risk ratio with 95% confidence intervals.

Continuous data

We did not include any continuous outcomes, however, if we do include them in future updates, we will use the mean difference if outcomes are measured in the same way between trials. We will use the standardised mean difference to combine trials that measure the same outcome, but use different methods.

Unit of analysis issues

Cluster‐randomised trials.

We did not identify any cluster‐randomised trials to include in the analyses. However, in future updates of the review, if we identify suitable cluster‐randomised trials, we will adjust their sample sizes or standard errors using the methods described in the Handbook Section 16.3.4 or 16.3.6 using an estimate of the intracluster correlation co‐efficient (ICC) derived from the trial (if possible), from a similar trial or from a study of a similar population. If we use ICCs from other sources, we will report this and conduct sensitivity analyses to investigate the effect of variation in the ICC. If we identify both cluster‐randomised trials and individually‐randomised trials, we plan to synthesise the relevant information. We will consider it reasonable to combine the results from both if there is little heterogeneity between the study designs and the interaction between the effect of intervention and the choice of randomisation unit is considered to be unlikely.

We will also acknowledge heterogeneity in the randomisation unit and perform a sensitivity or subgroup analysis to investigate the effects of the randomisation unit.

Cross‐over trials

Cross‐over trials were not eligible for this review.

Other unit of analysis issues

Multiple pregnancies.

Women with multiple pregnancies were not included in this review. If included in future updates, we will use cluster‐trial methods as described above to adjust the data. Babies from multiple pregnancies may be more likely to develop the same outcomes (non‐independence), so counting each as a separate data point may overestimate the sample size and make confidence intervals too narrow. We will regard each woman as a randomised cluster and use cluster‐trial methods to adjust outcomes for the baby.

Trials with more than two arms

If we had identified trials with more than two arms we would have pooled results using the methods set out in the Handbook (Higgins 2011) to avoid double‐counting.

Dealing with missing data

For included studies, levels of attrition were noted. In future updates, if more eligible studies are included, the impact of including studies with high levels of missing data in the overall assessment of treatment effect will be explored by using sensitivity analysis.

For all outcomes, analyses were carried out, as far as possible, on an intention‐to‐treat basis, i.e. we attempted to include all participants randomised to each group in the analyses. The denominator for each outcome in each trial was the number randomised minus any participants whose outcomes were known to be missing.

Assessment of heterogeneity

We assessed statistical heterogeneity in each meta‐analysis using the Tau², I² and Chi² statistics. We regarded heterogeneity as substantial if an I² was greater than 30% and either a Tau² was greater than zero, or there was a low P value (less than 0.10) in the Chi² test for heterogeneity. If we had identified substantial heterogeneity (above 30%), we would have explored it.

Assessment of reporting biases

In future updates, if there are 10 or more studies in the meta‐analysis, we will investigate reporting biases (such as publication bias) using funnel plots. We will assess funnel plot asymmetry visually. If asymmetry is suggested by a visual assessment, we will perform exploratory analyses to investigate it.

Data synthesis

We carried out statistical analysis using the Review Manager software ( RevMan 2014 ). We used fixed‐effect meta‐analysis for combining data where it was reasonable to assume that studies were estimating the same underlying treatment effect: i.e. where trials were examining the same intervention, and the trials’ populations and methods were judged sufficiently similar.

In future updates, if there is clinical heterogeneity sufficient to expect that the underlying treatment effects differed between trials, or if substantial statistical heterogeneity is detected, we will use random‐effects meta‐analysis to produce an overall summary, if an average treatment effect across trials is considered clinically meaningful. The random‐effects summary will be treated as the average range of possible treatment effects and we will discuss the clinical implications of treatment effects differing between trials. If the average treatment effect is not clinically meaningful, we will not combine trials. If we use random‐effects analyses, the results will be presented as the average treatment effect with 95% confidence intervals, and the estimates of Tau² and I².

Subgroup analysis and investigation of heterogeneity

We did not use subgroup analyses to investigate substantial heterogeneity. We carried out a clinical subgroup analyses on an issue of particular interest: women with no previous caesarean section versus women with previous caesarean section. This analysis was carried out for each review outcome. We assessed subgroup differences by interaction tests available within RevMan ( RevMan 2014 ). We reported the results of subgroup analyses quoting the Chi² statistic and P value, and the interaction test I² value.

Sensitivity analysis

We carried out sensitivity analyses to explore the effect of trial quality assessed by concealment of allocation with studies at high risk of allocation bias being excluded from the analyses in order to assess whether this makes any difference to the overall result. In future updates, if any trial is judged to be of poor quality due to being at high risk of bias for allocation concealment, high attrition rates, or both, we will also exclude these from the analysis.

Description of studies

Please see Characteristics of included studies and Characteristics of excluded studies for further details.

Results of the search

For this update, we assessed two reports of one trial ( Gaitan 2009 ) from a search of Cochrane Pregnancy and Childbirth's Trials Register (January 2017). In total, five trials are now included ( Crichton 1962 ; Gaitan 2009 ; Parsons 1985 ; Richards 1985 ; Thubisi 1993 ) and one is excluded ( Farrell 2002 ). See: Figure 1 .

Study flow diagram.

Included studies

Five trials with a total of 1159 women were included.

Study design

All included trials were two‐armed randomised controlled trials, using individual randomisation. Sample sizes were small and ranged from 102 ( Richards 1985 ) to 305 women ( Crichton 1962 ).

Trials were conducted in hospitals in South Africa ( Crichton 1962 ; Richards 1985 ; Thubisi 1993 ), USA ( Parsons 1985 ) and Spain ( Gaitan 2009 ).

Participants

Gaitan 2009 and Parsons 1985 only included nulliparous women in their trials, Crichton 1962 did not specify the parity of the women included, and Richards 1985 and Thubisi 1993 only included women with one previous lower segment caesarean section.

Gaitan 2009 and Parsons 1985 only randomised women who were being induced or augmented with oxytocin. Crichton 1962 randomised women when they were in labour and their doctor requested a pelvimetry. Both Richards 1985 and Thubisi 1993 performed pelvimetry at 36 weeks' gestation so women were randomised during pregnancy.

Interventions and comparisons

All of the trials included in the review examined X‐ray pelvimetry. We did not identify any trials comparing clinical pelvimetry with no pelvimetry, or examining other types of radiological pelvimetry.

Crichton 1962 included 305 women in labour whose attending doctors requested pelvimetry. Women were randomised to receive X‐ray pelvimetry or no pelvimetry during labour. No fetal heart rate monitoring was performed.

Parsons 1985 recruited 200 primigravid women who required induction of labour or augmentation of labour with oxytocin. All women received a clinical pelvimetry. Women were subsequently randomised by hospital number to either receive or not receive an X‐ray pelvimetry. Continuous fetal heart rate monitoring was done.

Richards 1985 included 102 women with one previous caesarean section (classical uterine incision being excluded). Women were randomised into two groups: the first group received an X‐ray pelvimetry at 36 weeks' gestation. If the pelvic inlet was less than 10.5 cm in the antero‐posterior diameter or less than 11.5 cm in the transverse diameter, an elective caesarean section was performed. The other women and the control group underwent a trial of scar, and had X‐ray pelvimetry postpartum as a comparison.

Thubisi 1993 randomised 288 women with one previous transverse lower segment caesarean section. The intervention group received an X‐ray pelvimetry at 36 weeks' gestation. A sagittal inlet of less than 11 cm, sagittal outlet of less than 10 cm, transverse inlet less than 11.5 cm, and transverse outlet (bispinous) less than 9 cm was an indication for caesarean section. The other women in the intervention group and the control group awaited a trial of scar.

Gaitan 2009 included 264 women. Women were randomised into two groups to either receive or not receive an X‐ray pelvimetry.

Crichton 1962 : outcomes were caesarean section/symphysiotomy, perinatal mortality, asphyxia and maternal survival.

Parsons 1985 : outcomes assessed were length of labour, length of rupture of membranes, length of oxytocin administration, type of birth, Apgar scores and birthweight.

Richards 1985 : outcomes measured were mode of birth, pelvimetry measurements, birthweight and average stay in hospital.

Thubisi 1993 : outcomes measured were caesarean section, perinatal mortality, birthweight, scar dehiscence, puerperal pyrexia, wound sepsis and blood transfusion.

Gaitan 2009 : outcomes measured were time from induction to birth of baby, method of birth, use of instruments during birth, any adverse effects and perinatal mortality.

Funding sources were not disclosed by any of the trialists.

Excluded studies

One trial was excluded: Farrell 2002 ; there were too few women recruited, study protocol was not adhered to, and the trial was stopped prior to completion due to inadequate randomisation.

Risk of bias in included studies

Please see Figure 2 and Figure 3 for a summary of 'Risk of bias' assessments.

'Risk of bias' summary: review authors' judgements about each risk of bias item for each included study.

'Risk of bias' graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.

In all studies selection bias cannot be excluded, although Richards 1985 and Thubisi 1993 randomised a more homogeneous group of women as they were not in labour at the time of randomisation.

Both Crichton 1962 and Richards 1985 risk of selection bias was assessed as being 'unclear' due to not enough information being provided in the papers. Parsons 1985 and Thubisi 1993 were assessed as high risk as Parsons 1985 allocated women by hospital number, and Thubisi 1993 'randomly' assigned women at the first antenatal visit to one of two consultant teams, allocated by admitting clerks who had no medical training and knowledge of how they would be managed. Gaitan 2009 used a random number table to allocate women into groups but allocation concealment is not mentioned adequately.

Crichton 1962 relied on the attending clinician to request a pelvimetry and Parsons 1985 included a group of women requiring augmentation of labour, indicating that labour was already not progressing as expected.

None of the trials blinded participants, care givers or outcome assessors. For this type of outcome, blinded would be very difficult.

Incomplete outcome data

Thubisi 1993 randomised 306 women but only followed up 288. This loss to follow‐up is relatively low but loss of two women in the pelvimetry group related to outcomes of the study (women opted for caesarean section). For this reason, Thubisi 1993 was assessed as being at unclear risk of attrition bias. Richards 1985 was also assessed as unclear due to missing totals in the results tables of the study.

All remaining trials were assessed to be at low risk of attrition bias as data were reported for all women who were randomised.

Selective reporting

Protocols were not available for any of the included studies. Crichton 1962 , Parsons 1985 , Richards 1985 and Thubisi 1993 did not pre‐specify outcomes in the methods text. Gaitan 2009 does not report all outcomes, however in is unclear if this is due to translation issues. All trials were assessed to be at unclear risk of reporting bias.

Other potential sources of bias

All the trials were assessed to be at unclear risk of other bias except for Parsons 1985 and Thubisi 1993 who were assessed to be at low risk of bias as the baseline characteristics of both groups were similar and there was no other evidence of bias. Crichton 1962 and Richards 1985 did not report any baseline characteristics, and Gaitan 2009 had some unclear discrepancy between totals in tables and in text though it was unclear if this were due to translation issues.

Effects of interventions

See: Table 1

Summary of findings 1

1 Most studies contributing data had design limitations. Two studies had serious design limitations (high risk of bias for sequence generation and allocation concealment) one of which contributed 37.4% of weight (‐2).

2 Most studies contributing data had design limitations. (‐1)

3 Wide confidence interval crossing the line of no effect, small sample size, few events and lack of precision. (‐2)

4 One study contributing data with serious design limitations. (‐2)

5 Very wide confidence intervals crossing the line of no effect, small sample size and few events. (‐2)

6 Study contributing 79.7% total weight has serious design limitations. (‐2)

X‐ray pelvimetry versus no X‐ray pelvimetry

All five trials assessed the rate of caesarean section as an outcome, including a total of 1159 women. Crichton 1962 reported caesarean section and symphysiotomy results combined, therefore data for both caesarean section and symphysiotomy are included in this analysis. No other study reported symphysiotomy.

Women who had X‐ray pelvimetry had a higher rate of caesarean section than those women who had no X‐ray pelvimetry. The risk ratio (RR) for caesarean section is 1.34 (95% confidence interval (CI) 1.19 to 1.52; 1159 women; 5 trials; low‐quality evidence ) Analysis 1.1 when compared to women who did not get an X‐ray pelvimetry. Quality of evidence as assessed using GRADE is low.

Comparison 1: X‐ray pelvimetry versus no X‐ray pelvimetry, Outcome 1: Caesarean section

Subgroup interaction tests suggest no clear differences in effects for women with previous versus women with no previous caesarean section (Test for subgroup differences: Chi² = 1.52, df = 1 (P = 0.22), I² = 34.1%). The two trials that only included women with a previous section ( Richards 1985 ; Thubisi 1993 ), performed elective caesarean sections on the women whose pelvic inlets did not satisfy pre‐specified requirements following antenatal X‐ray pelvimetry; all those who did satisfy requirements were left to go into spontaneous labour. A higher caesarean rate might therefore be expected. In future updates of this review it will be useful to analyse data for rates of elective and emergency caesarean sections separately.

All five trials assessed the perinatal mortality as an outcome, including a total of 1159 women. There is no clear difference in perinatal mortality between women who did and women who did not receive an X‐ray pelvimetry (RR 0.53, 95% CI 0.19 to 1.45; 1159 infants; 5 trials; very low‐quality evidence ) Analysis 1.2 . Quality of evidence as assessed using GRADE is very low.

Comparison 1: X‐ray pelvimetry versus no X‐ray pelvimetry, Outcome 2: Perinatal mortality

One trial including 288 women who all had a previous caesarean ( Thubisi 1993 ) assessed the incidence of puerperal pyrexia as an outcome after caesarean in both groups (women who did receive an X‐ray pelvimetry compared to women who did not). Little difference was found: RR 0.80 (95% CI 0.22 to 2.92; 288 women; 1 trial) Analysis 1.3 .

Comparison 1: X‐ray pelvimetry versus no X‐ray pelvimetry, Outcome 3: Puerperal pyrexia

One trial including 288 women ( Thubisi 1993 ) assessed the incidence of wound sepsis as an outcome after caesarean in both groups (women who did receive an X‐ray pelvimetry compared to women who did not). Little difference was found: RR 0.83 (95% CI 0.26 to 2.67; 288 women; 1 trial; very low‐quality evidence ) Analysis 1.4 . Quality of evidence as assessed using GRADE is very low.

Comparison 1: X‐ray pelvimetry versus no X‐ray pelvimetry, Outcome 4: Wound sepsis

One trial including 288 women ( Thubisi 1993 ) assessed the need for blood transfusion as an outcome in both groups (women who did receive an X‐ray pelvimetry compared to women who did not). No difference was found: RR 1.00 (95% CI 0.39 to 2.59; 288 women; 1 trial; very low‐quality evidence ) Analysis 1.5 . Quality of evidence as assessed using GRADE is very low.

Comparison 1: X‐ray pelvimetry versus no X‐ray pelvimetry, Outcome 5: Blood transfusion

Two trials including 390 women ( Richards 1985 ; Thubisi 1993 ) assessed the incidence of scar dehiscence as an outcome in women who had one previous transverse uterine segment caesarean section and underwent trial of scar. Little difference was found: RR 0.59 (95% CI 0.14 to 2.46; 390 women; 2 trials; v ery low‐quality evidence ) Analysis 1.6 . Quality of evidence as assessed using GRADE is very low.

Comparison 1: X‐ray pelvimetry versus no X‐ray pelvimetry, Outcome 6: Scar dehiscence

One trial including 305 infants ( Crichton 1962 ) assessed incidence of perinatal asphyxia. Little difference was found: RR 0.66 (95% CI 0.39 to 1.10; 305 infants; 1 trial) Analysis 1.7 .

Comparison 1: X‐ray pelvimetry versus no X‐ray pelvimetry, Outcome 7: Perinatal asphyxia

Admission to special care baby unit

One trial including 288 infants ( Thubisi 1993 ) assessed the need for admission to a special care baby unit. Little difference was found: RR 0.20 (95% CI 0.01 to 4.13; 288 infants; 1 trial; very low‐quality evidence ) Analysis 1.8 . Quality of evidence as assessed using GRADE is very low.

Comparison 1: X‐ray pelvimetry versus no X‐ray pelvimetry, Outcome 8: Admission to special care baby units

No trials assessed the Apgar score less than seven at five minutes as an outcome.

Women without previous caesarean section

Three trials included women with no previous caesarean section ( Crichton 1962 ; Gaitan 2009 ; Parsons 1985 ) with a total number of 769 women. There is a higher caesarean section rate (and symphysiotomy rate in Crichton 1962 ) in the X‐ray pelvimetry group (RR 1.24, 95% CI 1.02 to 1.52; 769 women; 3 trials). There is no difference in perinatal mortality (RR 0.64, 95% CI 0.21 to 1.90; 769 women; 3 trials). There was a slight decrease in perinatal asphyxia and perinatal mortality in Crichton 1962 , but this decrease in perinatal mortality was not observed in Parsons 1985 or Gaitan 2009 . Neither trial reported perinatal asphyxia. The decrease seen in Crichton 1962 could be due to chance or lack in fetal monitoring. None of these trials reported puerperal pyrexia, wound sepsis, blood transfusion, or admission to special care baby unit. Scar dehiscence was not relevant to these women.

Women with previous caesarean section

Two trials included women who had a previous transverse lower segment caesarean section ( Richards 1985 ; Thubisi 1993 ), with a total number of 390 women. There was an overall increase in the caesarean section rate in both studies in the X‐ray pelvimetry groups (RR 1.45, 95% CI 1.26 to 1.67; 390 women; 2 trials). There was a slight decrease in perinatal mortality, which could have occurred by chance, in Richards 1985 , but this was not observed in Thubisi 1993 where there were no perinatal deaths in either group (RR 0.19, 95% CI 0.01 to 3.91; 390 women; 2 trials). There were similar rates of scar dehiscence in the intervention and control groups (RR 0.59, 95% CI 0.14 to 2.46; 390 women; 2 trials). Thubisi 1993 reported a slight increase in admissions to special care baby units in the control group, but again these could have occurred by chance. Richards 1985 did not report this outcome. Only Thubisi 1993 reported puerperal pyrexia, wound sepsis and blood transfusion and did not find any difference between the groups.

We carried out sensitivity analysis for lack of allocation concealment. Parsons 1985 and Thubisi 1993 were assessed to be at high risk of selection bias and were removed from Analysis 1.1 : Caesarean section/symphysiotomy and Analysis 1.2 : Perinatal mortality. There were not sufficient data to remove these trials from the other outcomes and maintain a meaningful analysis.

For the outcome caesarean section/symphysiotomy, removing the trial data widened the CIs and lessened the effect slightly (RR 1.25, 95% CI 1.04 to 1.49), but the data still showed that women who had pelvimetry were more likely to have a caesarean section. Regarding the women without a previous caesarean section, removing Parsons 1985 meant that the CIs crossed the line of no effect (RR 1.19, 95% CI 0.96 to 1.47).

There were no perinatal deaths in either Parsons 1985 or Thubisi 1993 , so removing the data from the meta‐analysis made no difference to the overall relative risk.

X‐ray pelvimetry versus no pelvimetry or clinical pelvimetry is the only comparison included in this review due to the lack of trials identified that used other types of pelvimetry (other radiological examination).

Summary of main results

Five trials with a total of 1159 women were included. All used X‐ray pelvimetry to assess the pelvis. X‐ray pelvimetry versus no pelvimetry or clinical pelvimetry is the only comparison included in this review due to the lack of trials identified that used other types or pelvimetry.

Women who received an X‐ray pelvimetry, had a higher risk having a caesarean section, without a decrease in perinatal mortality. The control groups tended to a slightly raised perinatal mortality, but this could be due to chance. The numbers studied were insufficient to assess perinatal mortality adequately. No clear differences were found between groups for puerperal pyrexia, wound sepsis, blood transfusion, scar dehiscence, perinatal asphyxia or admission to special care baby unit. No trial reported Apgar score less than seven at five minutes.

Parsons 1985 explains the increased perinatal mortality and asphyxia in Crichton 1962 by the lack of electronic fetal monitoring available to the women in Crichton's trial. The two deaths in the study of Richards 1985 occurred in utero before the onset of labour.

Some of the outcomes in this review, relating to women with a previous caesarean, are difficult to interpret because they are mediated by another outcome, for example, wound sepsis and blood transfusion are only relevant to those women who have a caesarean section.

Overall completeness and applicability of evidence

The trials are compatible with respect to the common measures of outcome. The small number of trials included in this review address the research question and do not support the use of X‐ray pelvimetry, though they are of low quality, and there are no trials to assess the use of computed tomography (CT) or magnetic resonance imaging (MRI) pelvimetry. The paucity of trials assessing the effectiveness of all methods of pelvimetry, for both women with and without a previous caesarean, limits the applicability of this review. The majority of the few trials available are over 20 years old. This perhaps reflects how little pelvimetry is used by clinicians in current practice.

The trials were also conducted in a small number of countries (South Africa, Spain, and the USA) and therefore the findings may not be applicable to low‐income settings.

Quality of the evidence

All trial designs regarding treatment allocation were of poor quality, assessed as high or unclear risk of bias. None of the trials blinded participants, staff or outcome assessors. The trials were not well‐reported so it was difficult to assess the other 'Risk of bias' domains. The two trials in women with previous caesarean sections were performed at the same institution a few years apart. We have found that overall, the findings are at a moderate to high risk of bias. Please see Figure 2 for a summary of the risk of bias.

We used GRADEpro software to grade evidence for our selected outcomes; for caesarean section we rated the evidence low quality and all the other outcomes, perinatal mortality, wound sepsis, blood transfusion, scar dehiscence and admission to special care baby unit as very low quality. Downgrading was due to risk of bias relating to lack of allocation concealment and blinding, and imprecision of effect estimates. Please see Table 1 .

Potential biases in the review process

We took steps to reduce bias as we are aware of the potential to introduce bias throughout the process of writing the review. Two review authors assessed each study for possible inclusion, assessed the quality of the trials and extracted data independently. We recognise that assessing the quality of the trials can be subjective and that different people assessing risk of bias may have come up with different judgements.

Agreements and disagreements with other studies or reviews

The results of this review agree with another non‐Cochrane systematic review that looked at clinical interventions, including X‐ray pelvimetry, which increased vaginal birth after caesarean section (VBAC) ( Catling‐Paull 2011 ). Catling‐Paull 2011 found that X‐ray pelvimetry was a poor predictor of birth outcome, and that women who received pelvimetry were less likely to attempt a vaginal birth. Subsequently, the caesarean section rate was higher in the groups where women had pelvimetry.

Implications for practice

X‐ray pelvimetry versus no pelvimetry or clinical pelvimetry is the only comparison included in this review due to the lack of trials identified that used other types or pelvimetry (e.g. other radiological examinations). There is not enough evidence to support the use of X‐ray pelvimetry for deciding on the mode of delivery in women whose fetuses have a cephalic presentation, and the practice may be harmful to the mother by increasing the risk of having a caesarean section, without increasing the benefit to the fetus or neonate.

Implications for research

Further research should be directed towards defining whether there are specific clinical situations, for example, breech presentations, in which X‐ray pelvimetry can be shown to be of value. Newer methods of pelvimetry should be subjected to randomised trials to assess their value.

Further trials of X‐ray pelvimetry in cephalic presentations would be of value if large enough to assess the effect on perinatal mortality.

Anthony Todd, December 2020

It occurred to me that, having been involved with dogs with large heads and tiny pelvices that a simple measurement of the widest part of the pelvis may be related to the chances of dystocia. A basic measurement at any stage of pregnancy. or before. may predict with some, not all, as exceptions in nature are the rule, accuracy the chances of dystocia. these women could therefore be identified and prepared [in all sorts of ways] for the likelihood of dystocia.

Protocol first published: Issue 2, 1997 Review first published: Issue 2, 1997

Acknowledgements

Professor Justus Hofmeyr and Ms Cheryl Nikodem for assisting me with the study and teaching me (V Vannevel) the use of Review Manager. Thanks to Therese Dowswell (Cochrane Pregnancy and Childbirth) for her contribution in assessing studies and help preparing the 'Summary of findings' table for this update (2016).

This research was supported by a grant from the Department of Reproductive Health and Research, World Health Organization (WHO). The findings, interpretations and conclusions expressed in this paper are entirely those of the authors and should not be attributed in any manner whatsoever to WHO.

We thank El‐Marie Farrell for contributions to the previous update.

As part of the pre‐publication editorial process, this review has been commented on by three peers (an editor and two referees who are external to the editorial team), a member of Cochrane Pregnancy and Childbirth's international panel of consumers and the Group's Statistical Adviser.

This project was supported by the National Institute for Health Research, via Cochrane Infrastructure funding to Cochrane Pregnancy and Childbirth. The views and opinions expressed therein are those of the authors and do not necessarily reflect those of the Systematic Reviews Programme, NIHR, NHS or the Department of Health.

Edited (no change to conclusions)

Data and analyses

Comparison 1.

Characteristics of studies

Characteristics of included studies [ordered by study id].

Characteristics of excluded studies [ordered by study ID]

Differences between protocol and review

Title: We changed the title from Pelvimetry for fetal cephalic presentations at or near term to Pelvimetry for fetal cephalic presentations at or near term for deciding on mode of delivery .

Objectives: We removed assessing the effects of postnatal pelvimetry from the objectives as this could not impact on mode of delivery.

We also removed the following hypothesis.

• Information provided by pelvimetry in women without previous caesarean section is useful because it decreases the morbidity and mortality in the women and fetuses or neonates.
• Information provided by pelvimetry in women with previous caesarean section is useful because it decreases the morbidity and mortality in the women and fetuses or neonates.

We have clarified aspects in the section on Criteria for considering studies for this review, as follows:

All acceptably randomised comparisons of the use of pelvimetry in cephalic presentations in:

• women without previous caesarean section;
• women with previous caesarean section.

has changed to:

• Women without caesarean section;
• Women with previous caesarean section.

Pregnant women with singleton, cephalic presentation fetus who have or have not had a previous caesarean section. Studies which recruited women before, or during labour were included as well as women for spontaneous labour, induction or trial of scar after previous caesarean section.

Policy of elective caesarean section or trial of labour or scar depending on the prediction of pelvimetry as opposed to trial of labour or scar in all.

Outcomes: We changed ' Caesarean section/symphysiotomy' to ' Caesarean section'. Crichton 1962 only, reported the composite outcome of caesarean section/symphysiotomy, and did not report data for these outcomes separately. It is not clear how many symphysiotomies were performed in this trial and we could not report the data as two separate outcomes. We have documented this in the results section and in footnotes in Analysis 1.1 .

'Summary of findings' table: We assessed the trial quality by using GRADE assessment. This is documented in Table 1 .

Contributions of authors

V Vannevel assisted RC Pattinson with the 2016 update. V Vannevel analysed and interpreted the results, and prepared the update. A Cuthbert assessed studies for inclusion and prepared the 'Summary of findings' table.

Sources of support

Internal sources.

• University of Pretoria, South Africa

External sources

• South African Medical Research Council, South Africa
• Department of Reproductive Health and Research, World Health Organization, Switzerland
• UNDP‐UNFPA‐UNICEF‐WHO‐World Bank Special Programme of Research, Development and Research Training in Human Reproduction (HRP), Department of Reproductive Health and Research (RHR), World Health Organization, Switzerland

Declarations of interest

Robert C Pattinson: no conflict of interest. Anna Cuthbert: no conflict of interest. Valerie Vannevel: no conflict of interest.

References to studies included in this review

Crichton 1962 {published data only}.

• Crichton D. The accuracy and value of cephalopelvimetry . Journal of Obstetrics and Gynaecology of the British Commonwealth 1962; 69 :366-78. [ Google Scholar ]

Gaitan 2009 {published data only}

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Parsons 1985 {published data only}

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Richards 1985 {published data only}

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Thubisi 1993 {published data only}

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References to studies excluded from this review

Farrell 2002 {unpublished data only}.

• Volschenk S, Farrell E, Jeffery BS, Pattinson RC. Clinical pelvimetry as a predictor of vaginal delivery in women with one previous caesarean section . In: 20th Conference on Priorities in Perinatal Care in Southern Africa; 2001 March 6-9; KwaZulu-Natal, South Africa . 2002.

Additional references

Catling‐paull 2011.

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• Morris CW, Heggie JCP, Acton CM. Computed tomography pelvimetry: accuracy and radiation dose compared with conventional pelvimetry . Australasian Radiology 1993; 37 :186-91. [ PubMed ] [ Google Scholar ]

RevMan 2014 [Computer program]

• The Nordic Cochrane Centre, The Cochrane Collaboration Review Manager (RevMan) . Version 5.3. Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014.

Sporri 2002

• Sporri S, Thoeny HC, Raio L, Lachat R, Vock P, Schneider H. MR imaging pelvimetry: a useful adjunct in the treatment of women at risk for dystocia? American Journal of Roentgenology 2002; 179 :137-44. [ PubMed ] [ Google Scholar ]

van Ham 1997

• Ham MAEC, Dongen PWJ, Mulder J. Maternal consequences of caesarean section - A retrospective study of intra-operative and postoperative maternal complications of caesarean section during a 10-year period . European Journal of Obstetrics & Gynecology and Reproductive Biology 1997; 74 :1-6. [ PubMed ] [ Google Scholar ]

References to other published versions of this review

Pattinson 1997.

• Pattinson RC, Farrell EME. Pelvimetry for fetal cephalic presentations at or near term . Cochrane Database of Systematic Reviews 1997, Issue 2 . Art. No: CD000161. [DOI: 10.1002/14651858.CD000161] [ PMC free article ] [ PubMed ] [ CrossRef ] [ Google Scholar ]

Fetal Presentation, Position, and Lie (Including Breech Presentation)

• Key Points |

Abnormal fetal lie or presentation may occur due to fetal size, fetal anomalies, uterine structural abnormalities, multiple gestation, or other factors. Diagnosis is by examination or ultrasonography. Management is with physical maneuvers to reposition the fetus, operative vaginal delivery , or cesarean delivery .

Terms that describe the fetus in relation to the uterus, cervix, and maternal pelvis are

Fetal presentation: Fetal part that overlies the maternal pelvic inlet; vertex (cephalic), face, brow, breech, shoulder, funic (umbilical cord), or compound (more than one part, eg, shoulder and hand)

Fetal position: Relation of the presenting part to an anatomic axis; for vertex presentation, occiput anterior, occiput posterior, occiput transverse

Fetal lie: Relation of the fetus to the long axis of the uterus; longitudinal, oblique, or transverse

Normal fetal lie is longitudinal, normal presentation is vertex, and occiput anterior is the most common position.

Abnormal fetal lie, presentation, or position may occur with

Fetopelvic disproportion (fetus too large for the pelvic inlet)

Fetal congenital anomalies

Uterine structural abnormalities (eg, fibroids, synechiae)

Multiple gestation

Several common types of abnormal lie or presentation are discussed here.

Transverse lie

Fetal position is transverse, with the fetal long axis oblique or perpendicular rather than parallel to the maternal long axis. Transverse lie is often accompanied by shoulder presentation, which requires cesarean delivery.

Breech presentation

There are several types of breech presentation.

Frank breech: The fetal hips are flexed, and the knees extended (pike position).

Complete breech: The fetus seems to be sitting with hips and knees flexed.

Single or double footling presentation: One or both legs are completely extended and present before the buttocks.

Types of breech presentations

Breech presentation makes delivery difficult ,primarily because the presenting part is a poor dilating wedge. Having a poor dilating wedge can lead to incomplete cervical dilation, because the presenting part is narrower than the head that follows. The head, which is the part with the largest diameter, can then be trapped during delivery.

Additionally, the trapped fetal head can compress the umbilical cord if the fetal umbilicus is visible at the introitus, particularly in primiparas whose pelvic tissues have not been dilated by previous deliveries. Umbilical cord compression may cause fetal hypoxemia.

Predisposing factors for breech presentation include

Preterm labor

Uterine abnormalities

Fetal anomalies

If delivery is vaginal, breech presentation may increase risk of

Umbilical cord prolapse

Birth trauma

Perinatal death

Face or brow presentation

In face presentation, the head is hyperextended, and position is designated by the position of the chin (mentum). When the chin is posterior, the head is less likely to rotate and less likely to deliver vaginally, necessitating cesarean delivery.

Brow presentation usually converts spontaneously to vertex or face presentation.

Occiput posterior position

The most common abnormal position is occiput posterior.

The fetal neck is usually somewhat deflexed; thus, a larger diameter of the head must pass through the pelvis.

Progress may arrest in the second phase of labor. Operative vaginal delivery or cesarean delivery is often required.

Position and Presentation of the Fetus

If a fetus is in the occiput posterior position, operative vaginal delivery or cesarean delivery is often required.

In breech presentation, the presenting part is a poor dilating wedge, which can cause the head to be trapped during delivery, often compressing the umbilical cord.

For breech presentation, usually do cesarean delivery at 39 weeks or during labor, but external cephalic version is sometimes successful before labor, usually at 37 or 38 weeks.

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Abnormal Fetal lie, Malpresentation and Malposition

Original Author(s): Anna Mcclune Last updated: 1st December 2018 Revisions: 12

• 1 Definitions
• 2 Risk Factors
• 3.2 Presentation
• 3.3 Position
• 4 Investigations
• 5.1 Abnormal Fetal Lie
• 5.2 Malpresentation
• 5.3 Malposition

The lie, presentation and position of a fetus are important during labour and delivery.

In this article, we will look at the risk factors, examination and management of abnormal fetal lie, malpresentation and malposition.

Definitions

• Longitudinal, transverse or oblique
• Cephalic vertex presentation is the most common and is considered the safest
• Other presentations include breech, shoulder, face and brow
• Usually the fetal head engages in the occipito-anterior position (the fetal occiput facing anteriorly) – this is ideal for birth
• Other positions include occipito-posterior and occipito-transverse.

Note: Breech presentation is the most common malpresentation, and is covered in detail here .

Fig 1 – The two most common fetal presentations: cephalic and breech.

Risk Factors

The risk factors for abnormal fetal lie, malpresentation and malposition include:

• Multiple pregnancy
• Uterine abnormalities (e.g fibroids, partial septate uterus)
• Fetal abnormalities
• Placenta praevia
• Primiparity

Identifying Fetal Lie, Presentation and Position

The fetal lie and presentation can usually be identified via abdominal examination. The fetal position is ascertained by vaginal examination.

For more information on the obstetric examination, see here .

• Face the patient’s head
• Place your hands on either side of the uterus and gently apply pressure; one side will feel fuller and firmer – this is the back, and fetal limbs may feel ‘knobbly’ on the opposite side

Presentation

• Palpate the lower uterus (above the symphysis pubis) with the fingers of both hands; the head feels hard and round (cephalic) and the bottom feels soft and triangular (breech)
• You may be able to gently push the fetal head from side to side

The fetal lie and presentation may not be possible to identify if the mother has a high BMI, if she has not emptied her bladder, if the fetus is small or if there is polyhydramnios .

During labour, vaginal examination is used to assess the position of the fetal head (in a cephalic vertex presentation). The landmarks of the fetal head, including the anterior and posterior fontanelles, indicate the position.

Fig 2 – Assessing fetal lie and presentation.

Investigations

Any suspected abnormal fetal lie or malpresentation should be confirmed by an ultrasound scan . This could also demonstrate predisposing uterine or fetal abnormalities.

Abnormal Fetal Lie

If the fetal lie is abnormal, an external cephalic version (ECV) can be attempted – ideally between 36 and 38 weeks gestation.

ECV is the manipulation of the fetus to a cephalic presentation through the maternal abdomen.

It has an approximate success rate of 50% in primiparous women and 60% in multiparous women. Only 8% of breech presentations will spontaneously revert to cephalic in primiparous women over 36 weeks gestation.

Complications of ECV are rare but include fetal distress , premature rupture of membranes, antepartum haemorrhage (APH) and placental abruption. The risk of an emergency caesarean section (C-section) within 24 hours is around 1 in 200.

ECV is contraindicated in women with a recent APH, ruptured membranes, uterine abnormalities or a previous C-section .

Fig 3 – External cephalic version.

Malpresentation

The management of malpresentation is dependent on the presentation.

• Breech – attempt ECV before labour, vaginal breech delivery or C-section
• Brow – a C-section is necessary
• If the chin is anterior (mento-anterior) a normal labour is possible; however, it is likely to be prolonged and there is an increased risk of a C-section being required
• If the chin is posterior (mento-posterior) then a C-section is necessary
• Shoulder – a C-section is necessary

Malposition

90% of malpositions spontaneously rotate to occipito-anterior as labour progresses. If the fetal head does not rotate, rotation and operative vaginal delivery can be attempted. Alternatively a C-section can be performed.

• Usually the fetal head engages in the occipito-anterior position (the fetal occiput facing anteriorly) - this is ideal for birth

If the fetal lie is abnormal, an external cephalic version (ECV) can be attempted - ideally between 36 and 38 weeks gestation.

• Breech - attempt ECV before labour, vaginal breech delivery or C-section

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Presentation Scan

Checking the position of your baby to exclude breech presentation and fetal wellbeing

Scan containing important information before you finally meet you little one!

The main aim of the Presentation Scan is to diagnose breech position or other abnormalities in the baby’s position. The clinician assisting you with the delivery will use this information to prepare for your baby’s birth!

Normal pre-delivery baby cephalic position. Sometimes it is impossible to diagnose abnormal fetal positions without using ultrasound.

The significance of your baby’s position

The main aim of the Presentation Scan (or Pre Delivery Scan) is to diagnose breech position or other abnormalities in the baby’s position. We also perform thorough checkup of fetal growth and estimate fetal weight. We assess fetal wellbeing by umbilical artery and middle cerebral artery Dopplers.

Normally, a few weeks prior to birth, the baby will move into a delivery position where the head is positioned close to the birthing canal. However, about 3-4% of babies remain in a breech position. This is where the baby’s buttocks are positioned closest to the birthing canal, resembling a sitting position. Delivering a baby in breech position can be dangerous, but in roughly 50% of cases the position can be corrected by external cephalic version (ECV), which is a manual process performed by an obstetrician to turn the baby upside down in the womb allowing a head-first delivery. Alternatively, a caesarean section may be the safest option.

If your baby is in breech or other abnormal position just few weeks before your estimated due date you need to meet your obstetrics team to discuss the safest way of your delivery.

What do we look for in this scan

In most cases, an experienced midwife can recognise a breech position through an external manual examination of the baby, which is done by feeling for the baby’s orientation through the mother’s lower tummy. However, in some cases, the breech position remains unnoticed until active labour and/or rupture of membranes.

Thus, the main aim of our Baby Position Scan is to recognise an undiagnosed breech position.

Some of the other things we also look out for include:

• Monitoring the growth of the baby,

Perform ultrasound estimation of fetal weight (EFW),

• Baby’s well-being (such as movements, amniotic fluid, and fetal Dopplers),
• The placenta.

Graph showing normal fetal weight bounds throughout the pregnancy 

You have a question? We have an answer.

The best time for this scan is at 36 weeks of pregnancy.

By this time, if the baby’s head is not near the birthing canal, there is still time to discuss external cephalic version (ECV) or other delivery plans with your doctor or midwife.

The Baby Position Scan is less effective at detecting anomalies for the following reasons:

• The relatively big dimensions of the baby and the reduced amount of amniotic fluid by this stage of pregnancy severely hinder the resolution of the images and make it virtually impossible to perform a systematic examination of the baby,
• In the unfortunate event that a serious anomaly is detected, it would be too late to perform a full diagnostic work-up and proper counselling of the parents.
• If you are worried about late manifesting fetal anomalies, which can develop after the anomaly scan performed at 18-20 weeks, we strongly recommend getting our 3rd Trimester Anomaly Scan or/and Wellbeing Scan .

Usually performing a 4D scan during a Baby Position scan is ineffective because:

• The resolution of the image is severely affected by the naturally reduced amount of amniotic fluid by this stage of pregnancy,
• By this stage the majority of babies are facing their mother’s backs in preparation for delivery, meaning we would not be able to produce a useful scan.

We are happy to provide you the images of your baby, however in majority of the cases it will be impossible to obtain them. Babies at the end of the pregnancy usually facing backwards and it is not feasible to get any images.

We strongly recommend following the advice of the Royal College of Obstetricians and Gynaecologists (RCOG) and the Royal College of Midwives regarding the COVID-19 vaccines in pregnancy. It is strongly recommended to take your COVID-19 jabs, including the booster jabs, to protect yourself and your unborn baby from infection. If you have an underlying health condition, it is strongly advised to discuss your COVID-19 vaccination with your regular GP or healthcare provider.

Do you want to know more about our Fetal Presentation Scan?

• Vishal's account
• Prenatal Care

Fetal Cephalic Presentation During Pregnancy

What Is Cephalic Position?

Types of cephalic position, benefits of cephalic presentation, risks of cephalic position, what are some other positions and their associated risks, when does a foetus get into the cephalic position, how do you know if baby is in cephalic position, how to turn a breech baby into cephalic position, natural ways to turn a baby into cephalic position.

If your baby is moving around in the womb, it’s a good sign as it tells you that your baby is developing just fine. A baby starts moving around in the belly at around 14 weeks. And their first movements are usually called ‘ quickening’ or ‘fluttering’.

A baby can settle into many different positions throughout the pregnancy, and it’s alright. But it is only when you have reached your third and final trimester that the position of your baby in your womb will matter the most. The position that your baby takes at the end of the gestation period will most likely be how your baby will make its appearance in the world. Out of all the different positions that your baby can settle into, the cephalic position at 36 weeks is considered the best position. Read on to learn more about fetal cephalic presentation.

When it comes to cephalic presentation meaning, the following can be considered. A baby is in the cephalic position when he is in a head-down position. This is the best position for them to come out in. In case of a ‘cephalic presentation’, the chances of a smooth delivery are higher. This position is where your baby’s head has positioned itself close to the birth canal, and the feet and bottom are up. This is the best position for your baby to be in for safe and healthy delivery.

Your doctor will begin to keep an eye on the position of your baby at around 34 weeks to 36 weeks . The closer you get to your due date, the more important it is that your baby takes the cephalic position. If your baby is not in this position, your doctor will try gentle nudges to get your baby in the right position.

Though it is pretty straightforward, the cephalic position actually has two types, which are explained below:

1. Cephalic Occiput Anterior

Most babies settle in this position. Out of all the babies who settle in the cephalic position, 95% of them will settle this way. This is when a baby is in the head-down position but is facing the mother’s back. This is the preferred position as the baby is able to slide out more easily than in any other position.

2. Cephalic Occiput Posterior

In this position, the baby is in the head-down position but the baby’s face is turned towards the mother’s belly. This type of cephalic presentation is not the best position for delivery as the baby’s head could get stuck owing to its wide position. Almost 5% of the babies in cephalic presentation settle into this position. Babies who come out in this position are said to come out ‘sunny side up’.

Cephalic presentation, where the baby’s head is positioned down towards the birth canal, is the most common and optimal fetal presentation for childbirth. This positioning facilitates a smoother delivery process for both the mother and the baby. Here are several benefits associated with cephalic presentation:

1. Reduced risk of complications

Cephalic presentation decreases the likelihood of complications during labor and delivery , such as umbilical cord prolapse or shoulder dystocia, which can occur with other presentations.

2. Easier vaginal delivery

With the baby’s head positioned first, vaginal delivery is generally easier and less complicated compared to other presentations, resulting in a smoother labor process for the mother.

3. Lower risk of birth injuries

Cephalic presentation reduces the risk of birth injuries to the baby, such as head trauma or brachial plexus injuries, which may occur with other presentations, particularly breech or transverse positions.

4. Faster progression of labor

Babies in cephalic presentation often help to stimulate labor progression more effectively through their positioning, potentially shortening the duration of labor and reducing the need for medical interventions.

5. Better fetal oxygenation

Cephalic presentation typically allows for optimal positioning of the baby’s head, which facilitates adequate blood flow and oxygenation, contributing to the baby’s well-being during labor and delivery.

Factors such as the cephalic posterior position of the baby and a narrow maternal pelvis can increase the likelihood of complications during childbirth. Occasionally, infants in the cephalic presentation may exhibit a backward tilt of their heads, potentially leading to preterm delivery in rare instances.

In addition to cephalic presentation, there are several other fetal positions that can occur during pregnancy and childbirth, each with its own associated risks. These positions can impact the delivery process and may require different management strategies. Here are two common fetal positions and their associated risks:

1. Breech Presentation

• Babies in breech presentation, where the buttocks or feet are positioned to enter the birth canal first, are at higher risk of birth injuries such as hip dysplasia or brachial plexus injuries.
• Breech presentation can lead to complications during labor and delivery, including umbilical cord prolapse, entrapment of the head, or difficulty delivering the shoulders, necessitating interventions such as cesarean section.

2. Transverse Lie Presentation

• Transverse lie , where the baby is positioned sideways across the uterus, often leads to prolonged labor and increases the likelihood of cesarean section due to difficulties in the baby’s descent through the birth canal.
• The transverse position of the baby may result in compression of the umbilical cord during labor, leading to decreased oxygen supply and potential fetal distress. This situation requires careful monitoring and intervention to ensure the baby’s well-being.

When a foetus is moving into the cephalic position, it is known as ‘head engagement’. The baby stars getting into this position in the third trimester, between the 32nd and the 36th weeks, to be precise. When the head engagement begins, the foetus starts moving down into the pelvic canal. At this stage, very little of the baby is felt in the abdomen, but more is felt moving downward into the pelvic canal in preparation for birth.

You may think that in order to find out if your baby has a cephalic presentation, an ultrasound is your only option. This is not always the case. You can actually find out the position of your baby just by touching and feeling their movements.

By rubbing your hand on your belly, you might be able to feel their position. If your baby is in the cephalic position, you might feel their kicks in the upper stomach. Whereas, if the baby is in the breech position, you might feel their kicks in the lower stomach.

Even in the cephalic position, it may be possible to tell if your baby is in the anterior position or in the posterior position. When your baby is in the anterior position, they may be facing your back. You may be able to feel your baby move underneath your ribs. It is likely that your belly button will also pop out.

When your baby is in the posterior position, you will usually feel your baby start to kick you in your stomach. When your baby has its back pressed up against your back, your stomach may not look rounded out, but flat instead.

Mothers whose placentas have attached in the front, something known as anterior placenta , you may not be able to feel the movements of your baby as well as you might like to.

Breech babies can make things complicated. Both the mother and the baby will face some problems. A breech baby is positioned head-up and bottom down. In order to deliver the baby, the birth canal needs to open a lot wider than it has to in the cephalic position. Besides this, your baby can get an arm or leg entangled while coming out.

If your baby is in the breech position, there are some things that you can do to encourage the baby to get into the cephalic position. There are a few exercises that could help such as pelvic tilts , swimming , spending a bit of time upside down, and belly dancing are a few ways you can try yourself to get your baby into the head-down position .

If this is not working either, your doctor will try an ECV (External Cephalic Version) . Here, your doctor will be hands-on, applying some gentle, but firm pressure to your tummy. In order to reach a cephalic position, the baby will need to be rolled into a bottom’s up position. This technique is successful around 50% of the time. When this happens, you will be able to have a normal vaginal delivery.

Though it sounds simple enough to get the fetal presentation into cephalic, there are some risks involved with ECV. If your doctor notices your baby’s heart rate starts to become problematic, the doctor will stop the procedure right away.

Encouraging a baby to move into the cephalic position, where the head is down towards the birth canal, is often desirable for smoother labor and delivery. While medical interventions may be necessary in some cases, there are natural methods that pregnant individuals can try to help facilitate this positioning. Here are several techniques that may help turn a baby into the cephalic position:

1. Optimal Maternal Positioning

Maintaining positions such as kneeling, hands and knees, or pelvic tilts may encourage the baby to move into the cephalic position by utilizing gravity and reducing pressure on the pelvis.

2. Spinning Babies Techniques

Specific exercises and positions recommended by the Spinning Babies organization, such as Forward-Leaning Inversion or the Sidelying Release, aim to promote optimal fetal positioning and may help encourage the baby to turn cephalic.

3. Chiropractic Care or Acupuncture

Some individuals find that chiropractic adjustments or acupuncture sessions with qualified practitioners can help address pelvic misalignment or relax tight muscles, potentially creating more space for the baby to maneuver into the cephalic position.

4. Prenatal Yoga and Swimming

Engaging in gentle exercises like prenatal yoga or swimming may help promote relaxation, reduce stress on the uterine ligaments, and encourage the baby to move into the cephalic position naturally. These activities also support overall physical and mental well-being during pregnancy.

1. What factors influence whether my baby will be in cephalic presentation?

Several factors can influence your baby’s position during pregnancy, including the shape and size of your uterus, the strength of your abdominal muscles, the amount of amniotic fluid, and the position of the placenta . Additionally, your baby’s own movements and preferences play a role.

2. Is it necessary for my baby to be in cephalic presentation for a vaginal delivery?

While cephalic presentation is considered the optimal position for vaginal delivery, some babies born in non-cephalic presentations can still be safely delivered vaginally with the guidance of a skilled healthcare provider. However, certain non-cephalic presentations may increase the likelihood of needing a cesarean section.

3. What can I do to encourage my baby to stay in the cephalic presentation?

Maintaining good posture, avoiding positions that encourage the baby to settle into a breech or transverse lie, staying active with gentle exercises, and avoiding excessive reclining can all help encourage your baby to remain in the cephalic presentation. Additionally, discussing any concerns with your healthcare provider and following their recommendations can be beneficial.

This was all about fetus with cephalic presentation. Most babies get into the cephalic position on their own. This is the most ideal situation as there will be little to no complications during normal vaginal labour. There are different cephalic positions, but these should not cause a lot of issues. If your baby is in any position other than cephalic in pregnancy, you may need C-Section . Keep yourself updated on the smallest of progress during your pregnancy so that you are aware of everything that is going on. Go for regular check-ups as your doctor will be able to help you if a complication arises during acephalic presentation at 20, 28 and 30 weeks.

References/Resources:

1. Glezerman. M; Planned vaginal breech delivery: current status and the need to reconsider (Expert Review of Obstetrics & Gynecology); Taylor & Francis Online; https://www.tandfonline.com/doi/full/10.1586/eog.12.2 ; January 2014

2. Feeling your baby move during pregnancy; UT Southwestern Medical Center; https://utswmed.org/medblog/fetal-movements/

3. Fetal presentation before birth; Mayo Clinic; https://www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/in-depth/fetal-positions/art-20546850

4. Fetal Positions; Cleveland Clinic; https://my.clevelandclinic.org/health/articles/9677-fetal-positions-for-birth

5. FAQs: If Your Baby Is Breech; American College of Obstetricians and Gynecologists; https://www.acog.org/womens-health/faqs/if-your-baby-is-breech

6. Roecker. C; Breech repositioning unresponsive to Webster technique: coexistence of oligohydramnios (Journal of Chiropractic Medicine); Science Direct; https://www.sciencedirect.com/science/article/abs/pii/S1556370713000588 ; June 2013

7. Presentation and position of baby through pregnancy and at birth; Pregnancy, Birth & Baby; https://www.pregnancybirthbaby.org.au/presentation-and-position-of-baby-through-pregnancy-and-at-birth

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Breech presentation

• Overview  
• Theory  
• Diagnosis  
• Management  
• Follow up  
• Resources  

Breech presentation refers to the baby presenting for delivery with the buttocks or feet first rather than head.

Associated with increased morbidity and mortality for the mother in terms of emergency caesarean section and placenta praevia; and for the baby in terms of preterm birth, small fetal size, congenital anomalies, and perinatal mortality.

Incidence decreases as pregnancy progresses and by term occurs in 3% to 4% of singleton term pregnancies.

Treatment options include external cephalic version to increase the likelihood of vaginal birth or a planned caesarean section, the optimal gestation being 37 and 39 weeks, respectively.

Planned caesarean section is considered the safest form of delivery for infants with a persisting breech presentation at term.

Breech presentation in pregnancy occurs when a baby presents with the buttocks or feet rather than the head first (cephalic presentation) and is associated with increased morbidity and mortality for both the mother and the baby. [1] Cunningham F, Gant N, Leveno K, et al. Williams obstetrics. 21st ed. New York: McGraw-Hill; 1997. [2] Kish K, Collea JV. Malpresentation and cord prolapse. In: DeCherney AH, Nathan L, eds. Current obstetric and gynecologic diagnosis and treatment. New York: McGraw-Hill Professional; 2002. There is good current evidence regarding effective management of breech presentation in late pregnancy using external cephalic version and/or planned caesarean section.

History and exam

Key diagnostic factors.

• presence of risk factors
• buttocks or feet as the presenting part
• fetal head under costal margin
• fetal heartbeat above the maternal umbilicus

Other diagnostic factors

• subcostal tenderness
• pelvic or bladder pain

Risk factors

• premature fetus
• small for gestational age fetus
• nulliparity
• fetal congenital anomalies
• previous breech delivery
• uterine abnormalities
• abnormal amniotic fluid volume
• placental abnormalities
• female fetus

Diagnostic investigations

1st investigations to order.

• transabdominal/transvaginal ultrasound

Treatment algorithm

<37 weeks' gestation and in labour, ≥37 weeks' gestation not in labour, ≥37 weeks' gestation in labour: no imminent delivery, ≥37 weeks' gestation in labour: imminent delivery, contributors, natasha nassar, phd.

Associate Professor

Menzies Centre for Health Policy

Sydney School of Public Health

University of Sydney

Disclosures

NN has received salary support from Australian National Health and a Medical Research Council Career Development Fellowship; she is an author of a number of references cited in this topic.

Christine L. Roberts, MBBS, FAFPHM, DrPH

Research Director

Clinical and Population Health Division

Perinatal Medicine Group

Kolling Institute of Medical Research

CLR declares that she has no competing interests.

Jonathan Morris, MBChB, FRANZCOG, PhD

Professor of Obstetrics and Gynaecology and Head of Department

JM declares that he has no competing interests.

Peer reviewers

John w. bachman, md.

Consultant in Family Medicine

Department of Family Medicine

Mayo Clinic

JWB declares that he has no competing interests.

Rhona Hughes, MBChB

Lead Obstetrician

Lothian Simpson Centre for Reproductive Health

The Royal Infirmary

RH declares that she has no competing interests.

Brian Peat, MD

Director of Obstetrics

Women's and Children's Hospital

North Adelaide

South Australia

BP declares that he has no competing interests.

Lelia Duley, MBChB

Professor of Obstetric Epidemiology

University of Leeds

Bradford Institute of Health Research

Temple Bank House

Bradford Royal Infirmary

LD declares that she has no competing interests.

Justus Hofmeyr, MD

Head of the Department of Obstetrics and Gynaecology

East London Private Hospital

East London

South Africa

JH is an author of a number of references cited in this topic.

Differentials

• Transverse lie
• Caesarean birth
• Mode of term singleton breech delivery

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• Bahasa Malaysia

Pelvimetry for fetal cephalic presentations at or near term for deciding on mode of delivery

What is the issue?

Does the use of pelvimetry to assess the size of the woman's pelvis improve outcomes for baby and mother? Pelvimetry might identify babies whose heads are too big for their mother's pelvis. In this case, an elective caesarean section might improve the outcome. Forms of pelvimetry include radiological pelvimetry (X-ray, computerised tomography (CT) scan or magnetic resonance imaging (MRI)) and clinical examination of the woman. We planned to include all studies comparing the use of clinical or radiological (X-ray, CT or MRI) pelvimetry versus no pelvimetry, or different types of pelvimetry.

Why is this important?

Sometimes, normal labour does not progress because the baby's head is too big, or the pelvis of the mother is too small, for the baby to pass through. This is called "cephalo-pelvic disproportion" or "obstructed labour" which may lead to an emergency caesarean section with possible risks for both mother and baby. A pregnant mother or her caregiver might be worried that disproportion could occur and for this reason, pelvimetry can be performed either before or during labour. It can be undertaken by clinical examination, X-ray, CT-scan or MRI. Pelvimetry measures the diameters of the pelvis and the baby's head. However, doing a pelvimetry also has implications: clinical examination might be very uncomfortable for the mother, X-ray and CT-scanning might be harmful for the baby and MRI is very expensive. All of these techniques have to be performed meticulously by experienced and skilled people to have any real value.

If we could diagnose the disproportion accurately before birth using pelvimetry, we might reduce the need for an emergency caesarean section and plan an elective procedure, with better outcomes for the baby and less complications for the mother.

What evidence did we find?

We searched for evidence on 30th November 2016 and identified five trials with a total of 1159 pregnant women. All five trials used X-ray pelvimetry in comparison to no X-ray pelvimetry.

The women who received X-ray pelvimetry were more likely to have a caesarean section ( low-quality evidence ). Whether a woman had pelvimetry or not, we found no difference in the numbers of babies that died ( very low-quality evidence ), who did not have enough oxygen during labour, or were admitted to special care baby units ( very low-quality evidence ). For the women, no differences were found between numbers of women with wound sepsis, those who received a blood transfusion, or those whose caesarean section scar began to break down ( all very low-quality evidence ). Apgar score less than seven at five minutes was not reported in any study.

What does this mean?

There is too little evidence (the majority of which is low quality) to show whether measuring the size of the woman's pelvis (pelvimetry) is beneficial and safe when the baby is in a head-down position. The number of women having a caesarean section increased if women had X-ray pelvimetry but there was insufficient good-quality evidence to show if pelvimetry improves outcomes for the baby. More research is needed.

X-ray pelvimetry versus no pelvimetry or clinical pelvimetry is the only comparison included in this review due to the lack of trials identified that used other types or pelvimetry (other radiological examination or clinical pelvimetry versus no pelvimetry). There is not enough evidence to support the use of X-ray pelvimetry for deciding on mode of delivery in women whose fetuses have a cephalic presentation. Women who undergo an X-ray pelvimetry may be more likely to have a caesarean section.

Further research should be directed towards defining whether there are specific clinical situations in which pelvimetry can be shown to be of value. Newer methods of pelvimetry (CT, MRI) should be subjected to randomised trials to assess their value. Further trials of X-ray pelvimetry in cephalic presentations would be of value if large enough to assess the effect on perinatal mortality.

Pelvimetry assesses the size of a woman's pelvis aiming to predict whether she will be able to give birth vaginally or not. This can be done by clinical examination, or by conventional X-rays, computerised tomography (CT) scanning, or magnetic resonance imaging (MRI).

To assess the effects of pelvimetry (performed antenatally or intrapartum) on the method of birth, on perinatal mortality and morbidity, and on maternal morbidity. This review concentrates exclusively on women whose fetuses have a cephalic presentation.

We searched Cochrane Pregnancy and Childbirth Group's Trials Register (31 January 2017) and reference lists of retrieved studies.

Randomised controlled trials (including quasi-randomised) assessing the use of pelvimetry versus no pelvimetry or assessing different types of pelvimetry in women with a cephalic presentation at or near term were included. Cluster trials were eligible for inclusion, but none were identified.

Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. We assessed the quality of the evidence using the GRADE approach.

Five trials with a total of 1159 women were included. All used X-ray pelvimetry to assess the pelvis. X-ray pelvimetry versus no pelvimetry or clinical pelvimetry is the only comparison included in this review due to the lack of trials identified that examined other types of radiological pelvimetry or that compared clinical pelvimetry versus no pelvimetry.

The included trials were generally at high risk of bias. There is an overall high risk of performance bias due to lack of blinding of women and staff. Two studies were also at high risk of selection bias. We used GRADEpro software to grade evidence for our selected outcomes; for caesarean section we rated the evidence low quality and all the other outcomes (perinatal mortality, wound sepsis, blood transfusion, scar dehiscence and admission to special care baby unit) as very low quality. Downgrading was due to risk of bias relating to lack of allocation concealment and blinding, and imprecision of effect estimates.

Women undergoing X-ray pelvimetry were more likely to have a caesarean section (risk ratio (RR) 1.34, 95% confidence interval (CI) 1.19 to 1.52; 1159 women; 5 studies; low-quality evidence ). There were no clear differences between groups for perinatal outcomes: perinatal mortality (RR 0.53, 95% CI 0.19 to 1.45; 1159 infants; 5 studies; very low-quality evidence ), perinatal asphyxia (RR 0.66, 95% CI 0.39 to 1.10; 305 infants; 1 study), and admission to special care baby unit (RR 0.20, 95% CI 0.01 to 4.13; 288 infants; 1 study; very low-quality evidence ). Other outcomes assessed were wound sepsis (RR 0.83, 95% CI 0.26 to 2.67; 288 women; 1 study; very low-quality evidence ), blood transfusion (RR 1.00, 95% CI 0.39 to 2.59; 288 women; 1 study; very low-quality evidence ), and scar dehiscence (RR 0.59, 95% CI 0.14 to 2.46; 390 women; 2 studies; very low-quality evidence ). Again, no clear differences were found for these outcomes between the women who received X-ray pelvimetry and those who did not. Apgar score less than seven at five minutes was not reported in any study.