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What Is a Transverse Baby?

Although rare, a baby can be in a transverse lie position in the third trimester. Here's what that means and how it impacts delivery.

What Does Transverse Lie Mean?

• Risks and Complications
• How It Affects Pregnancy
• How It Affects Delivery

Can You Turn a Transverse Baby?

Westend61 / Getty Images

During pregnancy, the fetus moves around into different fetal positions , but most end up in the optimal head down, face down (cephalic occiput anterior) position in the last few weeks. When the fetus doesn’t move into the cephalic position for birth, it’s called fetal malpresentation.

One of the rarest positions is the transverse lie, where the fetus lies horizontally, often with one shoulder down or pressing against the birth canal. If you have a transverse baby at term, your provider will intervene because a vaginal delivery is not possible from this position.

Here’s all you need to know about transverse lie causes and how it may affect pregnancy and delivery.   

The transverse lie position is when the fetus lies across the pregnant person’s abdomen horizontally. Because the shoulder is often in the pelvic inlet, it is also sometimes called shoulder presentation. But the fetus can also have its back facing the birth canal or with feet and hands facing it.

The chances of the baby being in the sideways position at term are only around 1 in 300. But before term, at 32 weeks gestation, it’s as high as 1 in 50.

“Transverse lie is normal in the first trimester, common in the second, unusual in the third, and it’s not a position where vaginal birth is possible,” says Gail Tully, CPM , creator of Spinning Babies, a website that offers ways to ease a baby’s rotation through the pelvis based on its position. 

Causes of a Transverse Lie Position

The reason that a full-term baby is in a transverse lie position is often unknown, but there are some things that make it more likely. “Two of the most common risk factors for transverse lie at term include having extra amniotic fluid —often associated with diabetes but can be found on its own—and multiple gestation, such as twins or triplets,” says Layan Alrahmani, MD , maternal and fetal medicine specialist and assistant professor in obstetrics and gynecology at Loyola University Medical Center. 

Other Possible Risk Factors for a Transverse Baby

Other possible risk factors for transverse lie at term include: 

• Multiparity (previous pregnancies may lead to lax abdominal muscles)
• Premature labor
• Low amniotic fluid
• Placenta previa (the placenta is covering the pregnant person’s cervix)
• Pelvic, uterine, or fetal abnormalities (the latter is more common in primiparity, or first time births)

“Sometimes the baby is in the position for a reason,” says Karolyn Zambrotta, CNM , an obstetrics and gynecology specialist. “And after the doctor does the C-section you’ll find the problem, like a short or tight umbilical cord.” 

Possible Risks and Complications

Transverse lie at term can be risky for both the pregnant person and baby. 

“The transverse lie is frequently found early in the pregnancy. But if the baby does not change position, then a vaginal delivery cannot occur and we have to plan differently,” says Carolina Bibbo, MD , maternal-fetal medicine specialist at Brigham and Women’s Hospital.

“If the water were to break when the baby is in a transverse lie position, the cord could prolapse which is an obstetrical emergency.”  

Possible Complications of a Transverse Baby

Possible complications of the transverse lie position include:

• Birth defects 
• Birth trauma
• Obstructed labor
• Postpartum hemorrhage
• Umbilical cord prolapse
• Uterine rupture

How a Transverse Baby Affects Pregnancy

Some pregnant people feel abdominal and back pain during pregnancy when the fetus is in the sideways position. This is related to the uterus being stretched in different ways and can cause tightening in the ribs and cramping lungs. If your health care provider approves, you can try deep breathing and gentle yoga exercises at home to help relieve pain and encourage the fetus to turn. 

How a Transverse Baby Affects Delivery

If your health care provider still suspects the fetus is lying horizontal at 36 weeks, they'll order an ultrasound to confirm. Because a baby in the transverse lie position cannot be delivered vaginally, your providers will develop an alternate birth plan which can include a procedure called external cephalic version (ECV) to try and turn the fetus for vaginal delivery or a planned C-section.

In the case of multiples, triplets are almost always delivered via C-section. But for twins, if the first is head down, the second may drop into the cephalic position for normal delivery having more room after the first one comes out. “You could also try ECV or internal podalic version (IPV) on the second twin if needed,” says Dr. Alrahmani. “It’s really case by case and depends on the provider’s experience and preference, too.” 

After 34 weeks, it is very unlikely for a transverse baby to spontaneously move into the optimal head-down position for delivery. But, in some cases, it is possible to turn a transverse baby before labor.

Natural methods

If the fetus is not head down by 32 weeks, and there are no health concerns, midwives like Zambrotta might first recommend trying some natural techniques. As Dr. Bibbo notes, the data is limited for different approaches but certain yoga positions can help in some cases. 

Low-risk methods to encourage transverse babies to turn include:

• Sound or light (putting music or a bright light near the bottom of the uterus)
• Temperature (placing something cold like frozen peas behind the head and something warm like a rice-filled sock at the bottom of the stomach)
• Traditional Chinese medicine (TCM) like moxibustion , which involves heating acupuncture points with a stick of mugwort

Small studies have shown that the Webster technique, a gentle chiropractic approach that aligns the pelvis, can help correct fetal malpresentation. And the forward-leaning inversion, also developed by a chiropractor, is the most effective position for encouraging transverse lie babies to turn, according to Tully, who trains labor and delivery nurses on body balance techniques. 

Always speak with your health care professional before trying any methods to turn the fetus.

Medical intervention

If natural methods have not helped turn a transverse baby by 36 weeks, your provider will likely want to try an ECV in which they use their hands to put pressure on your belly to try and turn the fetus head down. This procedure should be done in a hospital setting to monitor the fetal heart rate, and for the rare case where an emergency C-section is needed.

Possible complications include placental abruption, fetal heart rate abnormalities (FHR), premature rupture of the membranes, preterm labor, fetal distress, and vaginal bleeding. 

ECV may not be safe if you have placenta previa, low amniotic fluid , a significant uterine abnormality, vaginal bleeding, high blood pressure, multiples (before delivery of the first twin), or fetal distress.

“In general, the success rate for external cephalic version is 60% of babies,” explains Dr. Bibbo. “But there’s a greater chance for ECV to turn a fetus in transverse lie than in a breech position .”

A baby in the transverse lie position cannot fit through the pregnant person’s pelvis. If gentle exercises, chiropractic techniques, or other natural methods don’t help your baby turn by 36 weeks, you may be a candidate for ECV to move the baby into the optimal head-down position for birth. But if ECV doesn’t work, then the health care provider will schedule a C-section .

Chapter 26: Transverse Lie . Oxorn-Foote Human Labor & Birth . 2023.

Effectiveness and Safety of Acupuncture and Moxibustion in Pregnant Women with Noncephalic Presentation: An Overview of Systematic Reviews . Evidence-Based Complementary and Alternative Medicine . 2019.

The Webster Technique: a chiropractic technique with obstetric implications . J Manipulative Physiol Ther . 2002.

External Cephalic Version . Obstetrics: Normal and Problem Pregnancies (Seventh Edition). 2017.

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What Is a Transverse Baby Position?

Why It Happens, How to Turn Your Baby, and Tips for a Safe Delivery

Causes and Risk Factors

Turning the fetus, complications, frequently asked questions.

A transverse baby position, also called transverse fetal lie, is when the fetus is sideways—at a 90-degree angle to your spine—instead of head up or head down. This development means that a vaginal delivery poses major risks to both you and the fetus.

Sometimes, a transverse fetus will turn itself into the head-down position before you go into labor. Other times, a healthcare provider may be able to turn the position.

If a transverse fetus can't be turned to the right position before birth, you're likely to have a cesarean section (C-section).

This article looks at causes and risk factors for a transverse baby position. It also covers how it's diagnosed and treated, the possible complications, and how you can plan ahead for delivery.

Marko Geber / Getty Images

How Common Is Transverse Baby Position?

An estimated 2% to 13% of babies are in an unfavorable position at delivery —meaning they're not in the head-down position .

Certain physiological issues can lead to a transverse fetal lie. These include:

• A bicornuate uterus : The uterus has a deep V in the top that separates the uterus into two sides; it may only be able to hold a near-term fetus sideways.
• Oligohydramnios or polyhydramnios : Abnormally low or high amniotic fluid volume (respectively).

Several risk factors can make it more likely for the fetus to be in a transverse lie, such as:

• The placenta being in an unusual position, such as blocking the opening to the cervix ( placenta previa ), which doesn't allow the fetus to reach the head-down position
• Going into labor early, before the fetus has had a chance to get into the right position
• Being pregnant with twins or other multiples, as the uterus is crowded and may not allow for much movement
• An abnormal pelvic structure that limits fetal movement
• Having a cyst or fibroid tumor blocking the cervix

Transverse fetal positioning is also more common after your first pregnancy.

It’s not uncommon for a fetus to be in a transverse position during the earlier stages of pregnancy. In most cases, though, they shift on their own well before labor begins. The transverse fetal position doesn't cause any signs or symptoms.

Healthcare professionals diagnose a transverse lie through an examination called Leopold’s Maneuvers. That involves feeling your abdomen to determine the fetal position. It's usually confirmed by an ultrasound.

You may also discover a transverse fetal lie during a routine ultrasound.

Timing of Transverse Position Diagnosis

The ultrasound done at your 36-week checkup lets your healthcare provider see the fetal position as you get closer to labor and delivery. If it's still a transverse lie at that time, your medical team will look at options for the safest labor and delivery.

Approximately 97% of deliveries involve a fetus positioned with the head down, in the best position to slide out. That makes a vaginal delivery easier and safer.

A transverse position only happens in about 1% of deliveries. In that position, the shoulder, arm, or trunk of the fetus may present first. This isn't a good scenario for either of you because a vaginal delivery is nearly impossible.

In these cases, you have two options:

• Turning the fetal position
• Having a C-section

If the fetus is in a transverse lie late in pregnancy, you or your healthcare provider may be able to change the position. Turning into the proper head-down position may help you avoid a C-section.

Medical Options

A healthcare provider can use one of the following techniques to attempt re-positioning a fetus:

• External cephalic version (ECV) : This procedure typically is performed at or after 36 weeks of pregnancy; involves using pressure on your abdomen where the fetal head and buttocks are.
• Webster technique : This is a chiropractic method in which a healthcare professional moves your hips to allow your uterus to relax and make more room for the fetus to move itself. (Note: No evidence supports this method.)

A 2020 study reported a 100% success rate for trained practitioners who used turning to change a transverse fetal lie. Real-world success rates are closer to 60%.

At-Home Options

You may be able to encourage a move out of the transverse position at home. You can try:

• Getting on your hands and knees and gently rocking back and forth
• Lying on your back with your knees bent and feet flat on the floor, then pushing your hips up in the air (bridge pose)
• Talking or playing music to stimulate the fetus to become more active
• Applying some cold to your abdomen where the fetal head is, which may make them want to move away from it

These methods may or may not work for you. While there's anecdotal evidence that they sometimes work, they haven't been researched.

Talk to your healthcare provider before attempting any of these techniques to ensure you're not doing anything unsafe.

Can Babies Go Back to Transverse After Being Turned?

Even if the fetus does change position or is successfully moved, it is possible that it could return to a transverse position prior to delivery.

Whether your child is born via C-section or is successfully moved so you can have a vaginal delivery, potential complications remain.

Cesarean Sections

C-sections are extremely common and are generally safe for both you and the fetus. Still, some inherent risks are associated with the procedure, as there are with any surgery.

The transverse position can force the surgeon to make a different type of incision, as the fetal lie may be right where they'd usually cut. Possible C-section complications for you can include:

• Increased bleeding
• Bladder or bowel injury
• Reactions to medicines
• Blood clots
• Death (very rare)

In rare cases, a C-section can result in potential complications for the baby , including:

• Breathing problems, if fluid needs to be cleared from their lungs

Most C-sections are safe and result in a healthy baby and parent. In some situations, a surgical delivery is the safest option available.

Vaginal Delivery

If the fetus is successfully moved out of the transverse lie position, you'll likely be able to deliver it vaginally. However, a few complications are possible even after the fetus has been moved:

• Labor typically takes longer.
• Your baby’s face may be swollen and appear bruised for a few days.
• The umbilical cord may be compressed, potentially causing distress and leading to a C-section.

Studies suggest that ECV is safe, effective, and may help lower the C-section rate.

Planning Ahead

As with any birth, if you experience a transverse fetal position, you should work with your healthcare provider to develop a delivery plan. If the transverse position has been maintained throughout the pregnancy, the medical team will evaluate the position at about 36 weeks and make plans accordingly.

Remember that even if the fetal head is down late in pregnancy, things can change quickly during labor and delivery. That means it's worthwhile to discuss options for different types of delivery in case they become necessary.

A transverse baby position, or transverse fetal lie, is the term for a fetus that's lying sideways in the uterus. Vaginal delivery usually isn't possible in these cases.

If the fetus is in this position near the time of delivery, the options are to turn it to make vaginal delivery possible or to have a C-section. A trained healthcare provider can use turning techniques. You may also be able to get the fetus to turn at home with some simple techniques.

Both C-section and vaginal delivery pose a risk of certain complications. However, these problems are rare and the vast majority of deliveries end with a healthy baby and parent.

A Word From Verywell

Pregnancy comes with many unknowns, and the surprises can continue up through labor and delivery.

Talking to your healthcare provider early on about possible scenarios can give you time to think about possible outcomes. This helps to avoid a situation where you’re considering risks and benefits during labor when quick decisions need to be made.

Ideally, a baby should be in the cephalic position (head down) at 32 weeks. If not, a doctor will examine the fetal position at around the 36-week mark and determine what should happen next to ensure a smooth delivery. Whether this involves a cesarian section will depend on the specific case.

Less than 1% of babies are born in the transverse position. In many cases, a doctor might recommend a cesarian delivery to ensure a more safe delivery. The risk of giving birth in the transverse lie position is greater before a due date or if twins or triplets are also born.

A planned cesarian section, or C-section, is typically performed in the 39th week of gestation. This is done so the fetus is given enough time to grow and develop so that it is healthy.

In some cases, a doctor may perform an external cephalic version (ECV) to change a transverse fetal lie. This involves the doctor using their hands to apply firm pressure to the abdomen so the fetus is moved into the cephalic (head-down) position.

Most attempts of ECV are successful, but there is a chance the fetus can move back to its previous position; in these cases, a doctor can attempt ECV again.

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

Tempest N, Lane S, Hapangama D.  Babies in occiput posterior position are significantly more likely to require an emergency cesarean birth compared with babies in occiput transverse position in the second stage of labor: a prospective observational study .  Acta Obstet Gynecol Scand . 2020;99(4):537-545. doi:10.1111/aogs.13765

National Institutes of Health, U.S. National Library of Medicine: MedlinePlus. Congenital uterine anomalies .

Figueroa L, McClure EM, Swanson J, et al.  Oligohydramnios: a prospective study of fetal, neonatal and maternal outcomes in low-middle income countries .  Reprod Health.  2020;17 (article 19). doi:10.1186/s12978-020-0854-y

National Institutes of Health, U.S. National Library of Medicine: MedlinePlus. Placenta previa .

National Institutes of Health, U.S. National Library of Medicine: MedlinePlus. Your baby in the birth canal .

Van der Kaay DC, Horsch S, Duvekot JJ.  Severe neonatal complication of transverse lie after preterm premature rupture of membranes .  BMJ Case Rep . 2013;bcr2012008399. doi:10.1136/bcr-2012-008399

Oyinloye OI, Okoyomo AA.  Longitudinal evaluation of foetal transverse lie using ultrasonography .  Afr J Reprod Health ; 14(1):129-133.

Nishikawa M, Sakakibara H. Effect of nursing intervention program using abdominal palpation of Leopold’s maneuvers on maternal-fetal attachment .  Reprod Health  2013;10 (article 12). doi.org/10.1186/1742-4755-10-12

National Institutes of Health, U.S. National Library of Medicine: MedlinePlus. Delivery presentations .

Dalvi SA. Difficult deliveries in Cesarean section .  J Obstet Gynaecol India . 2018;68(5):344-348. doi:10.1007/s13224-017-1052-x

Zhi Z, Xi L. Clinical analysis of 40 cases of external cephalic version without anesthesia .  J Int Med Res . 2021;49(1):300060520986699. doi:10.1177/0300060520986699

National Institutes of Health, U.S. National Library of Medicine: MedlinePlus. Questions to ask your doctor about labor and delivery .

Nemours KidsHealth. Cesarean sections .

By Elizabeth Yuko, PhD Yuko has a doctorate in bioethics and medical ethics and is a freelance journalist based in New York.

• Third Trimester
• Labor & Delivery

What to Know About the Transverse Baby Position

Babies like to kick , do somersaults and perform acrobatics in utero during pregnancy ( especially when you’re trying to sleep, of course). But toward the end of the third trimester, they tend to settle into a vertical and head-down (as opposed to breech ) position— usually , that is. Once in a while, baby stays put in the transverse baby position: In other words, they remain horizontal. But what does this mean for your labor and delivery experience? Read on to find out the potential risks and complications of the transverse baby position, how to try to turn a transverse baby and more.

What Is a Transverse Baby?

A transverse baby is positioned horizontally. Basically, they’re resting side-to-side instead of up-and-down in the uterus, according to the Icahn School of Medicine at Mount Sinai in New York City. Transverse lie is more common when you deliver before your due date , or have twins or triplets. While many babies are horizontal early on in pregnancy, most flip vertically toward the end of gestation. In fact, less than 1 percent of babies are in a transverse position by the time of delivery.

What Are Transverse Lie Baby Symptoms?

It’s not always easy to spot signs of transverse baby yourself, says Andrea Braden , MD, IBCLC, an ob-gyn, lactation consultant and CEO and co-founder of lactation company Lybbie . Typically, she says, you’ll notice a wideness in the center of your abdomen if baby is transverse.

Here are some other transverse lie baby symptoms to look out for, according to Ellen Smead , CNM, a certified nurse-midwife at Pediatrix Medical Group in Atlanta:

• The top part of your uterus might feel flatter and be positioned lower in your abdomen
• You might feel baby stretching out to the sides, but not top-to-bottom
• There may be an improvement in your breathing due to baby’s position

Keep in mind that where baby’s kicking isn’t always a reliable predictor of transverse baby position. “Feet can kick in all different directions,” says Braden. “Sometimes their feet are at their heads, and sometimes they’re out to the side and sometimes they’re down below.”

Causes of Transverse Baby Position

A transverse baby position can happen for both anatomical reasons or circumstances, like having had many children. Here are the most common reasons, according to experts:

The expecting person’s anatomy. Narrow hips can mean less space near the pelvic opening, which might make it harder for baby to flip vertically, says Braden.

Uterine fibroids. Uterine fibroids are ( generally harmless ) growths that can take up space in the uterus and limit baby’s movement, notes Smead.

Uterus shape. Uteruses with a heart shape or a slight separation in the middle can increase the chance that baby will settle sideways, says Smead.

Multiple past pregnancies. A uterus that has supported the growth of several children can sometimes be more elastic, and baby can then move, turn and change positions frequently as there’s more room and ability to do so, explains Smead.

It’s important to note that, more often than not, the transverse baby position is temporary. “It’s pretty common to have a baby transverse at different points throughout the pregnancy,” reassures Braden. She adds that, sometimes, babies hang out horizontally for a bit before eventually going vertical and head-down. “If they’re moving between breech to cephalic, or head-down, that transitional point in-between might have baby set up in a transverse way,” she says.

Potential Risks and Complications of Having a Transverse Baby

A transverse baby increases the risk of umbilical cord prolapse (when the umbilical cord comes out before baby), says Braden. This can be an emergency situation because it can cut off oxygen supply to baby. If labor begins when baby is still in transverse lie, a c-section is generally necessary, says Smead.

Some practitioners will try to turn baby first “if it’s not a difficult reach, and if there’s enough fluid around baby,” says Braden. “Otherwise, a lot of people will just move towards a c-section to prevent breaking water and having a cord prolapse-type of complication.”

How to Turn a Transverse Baby

There are some things you can do to help baby move from a transverse position into a vertical one. Options include gentle movements at home and medical interventions when necessary. Consult with your medical provider if you’re unsure of which method to choose.

Safe DIY ways to encourage transverse baby to turn

At home, pregnant people can try a couple of things to encourage baby to move into an up-and-down position. “[Lean] far forward over a couch or chair and [rock] the hips while gently massaging the sides of the abdomen,” says Smead. “Usually positioning and stretches involving inversion, or having the hips and bottom higher than the belly, encourage changing fetal position.”

Medical interventions to get a transverse baby to turn

Your provider can also try out a few things to help turn baby. One is an external cephalic version (ECV). The Cleveland Clinic notes that with an ECV, a prenatal specialist will place their hands on the belly to twist and turn baby to a head-down position gently. The entire procedure is done externally by applying firm pressure to the stomach. “Typically, you want to do this when you’re past 37 weeks, but you don’t quite want to be 39 weeks where the baby is really settled into position,” says Braden. Studies show that ECV has a success rate of 59.7 percent .

Another intervention is the Webster method, in which a chiropractor focuses on adjusting your hips and pelvis to encourage more space for baby to turn head-down, says Smead. “This often requires several sessions over a week or more to get the desired outcome,” she adds.

It’s important to remember that a transverse baby at delivery is very rare, and that in the vast majority of cases, baby will flip on their own before making their debut. But if baby stays transverse, your provider will recommend the optimal option for you and your little one.

FAQ About Transverse Lie Baby

You might have a few remaining questions about the transverse baby position. Here are some more things you might want to know.

What are all the possible fetal positions?

The most common delivery presentation, according to Mount Sinai, is cephalic, or head-down. In about 3 percent of cases, babies present as breech, or feet-down. A transverse presentation occurs in less than 1 percent of cases.

Is transverse position dangerous for baby?

Babies often move into the transverse position throughout pregnancy. But if baby settles into a transverse position toward the end of the third trimester, this can increase the risk of umbilical cord prolapse or c-section during labor.

When do transverse babies typically turn?

According to the Cleveland Clinic, most babies assume a head-down position by 36 weeks of pregnancy.

How should you sleep with a transverse baby?

There’s not much you can do while sleeping to help baby turn, says Braden. But sleeping on your side can help you feel more comfortable during pregnancy, notes Smead. “This position involves lying on one side with your top leg bent and pulled up as far as you can comfortably stretch over a pillow in front of your belly,” she says.

Where do you feel kicks with a transverse baby?

You could feel baby kicks anywhere with a transverse baby, notes Braden. A better sign of the transverse baby position is where the head and bottom are located, she says.

When is a c-section necessary for a transverse baby?

A c-section is often necessary for a transverse baby after other options—such as turning the baby—have been exhausted. “Often it’s important to recognize the transverse baby well before this time and have discussions about delivery mode prior,” says Smead. “Planning for a c-section is a good idea so that all involved can prepare. However, that doesn’t mean that the baby couldn’t turn on its own or in response to interventions before that time.”

Please note: The Bump and the materials and information it contains are not intended to, and do not constitute, medical or other health advice or diagnosis and should not be used as such. You should always consult with a qualified physician or health professional about your specific circumstances.

Plus, more from The Bump:

Quickening in Pregnancy: When Can You Feel Baby Move and Kick?

What Does It Mean to Have a Breech Baby?

What to Know About C-Section Procedures

Ellen Smead , CNM, is a certified nurse-midwife at Pediatrix Medical Group in Atlanta, Georgia. She graduated from Emory University in 2011 and is an advanced practice midwife with the American Midwifery Certification Board.

Andrea Braden , MD, FACOG, IBCLC, is an ob-gyn, breastfeeding medicine specialist, board-certified lactation consultant and CEO and co-founder of the lactation company Lybbie . She earned her medical degree from the University of South Alabama School of Medicine.

Icahn School of Medicine at Mount Sinai, Your Baby In the Birth Canal

Mayo Clinic, Uterine Fibroids , September 2023

Cleveland Clinic, External Cephalic Version (ECV) , May 2022

Cureus, Assessment of the Successful External Cephalic Version Prognostic Parameters Effect on Final Mode of Delivery , July 2021

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

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 .

• Key Points |

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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