what is the normal fetal presentation

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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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Breech, posterior, transverse lie: What position is my baby in?

Fetal presentation, or how your baby is situated in your womb at birth, is determined by the body part that's positioned to come out first, and it can affect the way you deliver. At the time of delivery, 97 percent of babies are head-down (cephalic presentation). But there are several other possibilities, including feet or bottom first (breech) as well as sideways (transverse lie) and diagonal (oblique lie).

Fetal presentation and position

During the last trimester of your pregnancy, your provider will check your baby's presentation by feeling your belly to locate the head, bottom, and back. If it's unclear, your provider may do an ultrasound or an internal exam to feel what part of the baby is in your pelvis.

Fetal position refers to whether the baby is facing your spine (anterior position) or facing your belly (posterior position). Fetal position can change often: Your baby may be face up at the beginning of labor and face down at delivery.

Here are the many possibilities for fetal presentation and position in the womb.

Medical illustrations by Jonathan Dimes

Head down, facing down (anterior position)

A baby who is head down and facing your spine is in the anterior position. This is the most common fetal presentation and the easiest position for a vaginal delivery.

This position is also known as "occiput anterior" because the back of your baby's skull (occipital bone) is in the front (anterior) of your pelvis.

Head down, facing up (posterior position)

In the posterior position , your baby is head down and facing your belly. You may also hear it called "sunny-side up" because babies who stay in this position are born facing up. But many babies who are facing up during labor rotate to the easier face down (anterior) position before birth.

Posterior position is formally known as "occiput posterior" because the back of your baby's skull (occipital bone) is in the back (posterior) of your pelvis.

Frank breech

In the frank breech presentation, both the baby's legs are extended so that the feet are up near the face. This is the most common type of breech presentation. Breech babies are difficult to deliver vaginally, so most arrive by c-section .

Some providers will attempt to turn your baby manually to the head down position by applying pressure to your belly. This is called an external cephalic version , and it has a 58 percent success rate for turning breech babies. For more information, see our article on breech birth .

Complete breech

A complete breech is when your baby is bottom down with hips and knees bent in a tuck or cross-legged position. If your baby is in a complete breech, you may feel kicking in your lower abdomen.

Incomplete breech

In an incomplete breech, one of the baby's knees is bent so that the foot is tucked next to the bottom with the other leg extended, positioning that foot closer to the face.

Single footling breech

In the single footling breech presentation, one of the baby's feet is pointed toward your cervix.

Double footling breech

In the double footling breech presentation, both of the baby's feet are pointed toward your cervix.

Transverse lie

In a transverse lie, the baby is lying horizontally in your uterus and may be facing up toward your head or down toward your feet. Babies settle this way less than 1 percent of the time, but it happens more commonly if you're carrying multiples or deliver before your due date.

If your baby stays in a transverse lie until the end of your pregnancy, it can be dangerous for delivery. Your provider will likely schedule a c-section or attempt an external cephalic version , which is highly successful for turning babies in this position.

Oblique lie

In rare cases, your baby may lie diagonally in your uterus, with his rump facing the side of your body at an angle.

Like the transverse lie, this position is more common earlier in pregnancy, and it's likely your provider will intervene if your baby is still in the oblique lie at the end of your third trimester.

Was this article helpful?

What to know if your baby is breech

What's a sunny-side up baby?

What happens to your baby right after birth

How your twins’ fetal positions affect labor and delivery

BabyCenter's editorial team is committed to providing the most helpful and trustworthy pregnancy and parenting information in the world. When creating and updating content, we rely on credible sources: respected health organizations, professional groups of doctors and other experts, and published studies in peer-reviewed journals. We believe you should always know the source of the information you're seeing. Learn more about our editorial and medical review policies .

Ahmad A et al. 2014. Association of fetal position at onset of labor and mode of delivery: A prospective cohort study. Ultrasound in obstetrics & gynecology 43(2):176-182. https://www.ncbi.nlm.nih.gov/pubmed/23929533 Opens a new window [Accessed September 2021]

Gray CJ and Shanahan MM. 2019. Breech presentation. StatPearls.  https://www.ncbi.nlm.nih.gov/books/NBK448063/ Opens a new window [Accessed September 2021]

Hankins GD. 1990. Transverse lie. American Journal of Perinatology 7(1):66-70.  https://www.ncbi.nlm.nih.gov/pubmed/2131781 Opens a new window [Accessed September 2021]

Medline Plus. 2020. Your baby in the birth canal. U.S. National Library of Medicine. https://medlineplus.gov/ency/article/002060.htm Opens a new window [Accessed September 2021]

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StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-.

StatPearls [Internet].

Delivery, face and brow presentation.

Julija Makajeva ; Mohsina Ashraf .

Affiliations

Last Update: January 9, 2023 .

• Continuing Education Activity

Face and brow presentation is a malpresentation during labor when the presenting part is either the face or, in the case of brow presentation, it is the area between the orbital ridge and the anterior fontanelle. This activity reviews the evaluation and management of these two presentations and explains the role of the interprofessional team in managing delivery safely for both the mother and the baby.

• Describe the mechanism of labor in the face and brow presentation.
• Summarize potential maternal and fetal complications during the face and brow presentations.
• Review different management approaches for the face and brow presentation.
• Outline some interprofessional strategies that will improve patient outcomes in delivery cases with face and brow presentation issues.
• Introduction

The term presentation describes the leading part of the fetus or the anatomical structure closest to the maternal pelvic inlet during labor. The presentation can roughly be divided into the following classifications: cephalic, breech, shoulder, and compound. Cephalic presentation is the most common and can be further subclassified as vertex, sinciput, brow, face, and chin. The most common presentation in term labor is the vertex, where the fetal neck is flexed to the chin, minimizing the head circumference.

Face presentation – an abnormal form of cephalic presentation where the presenting part is mentum. This typically occurs because of hyperextension of the neck and the occiput touching the fetal back. Incidence of face presentation is rare, accounting for approximately 1 in 600 of all presentations. [1] [2] [3]

In brow presentation, the neck is not extended as much as in face presentation, and the leading part is the area between the anterior fontanelle and the orbital ridges. Brow presentation is considered the rarest of all malpresentation with a prevalence of 1 in 500 to 1 in 4000 deliveries. [3]

Both face and brow presentations occur due to extension of the fetal neck instead of flexion; therefore, conditions that would lead to hyperextension or prevent flexion of the fetal neck can all contribute to face or brow presentation. These risk factors may be related to either the mother or the fetus. Maternal risk factors are preterm delivery, contracted maternal pelvis, platypelloid pelvis, multiparity, previous cesarean section, black race. Fetal risk factors include anencephaly, multiple loops of cord around the neck, masses of the neck, macrosomia, polyhydramnios. [2] [4] [5]

These malpresentations are usually diagnosed during the second stage of labor when performing a digital examination. It is possible to palpate orbital ridges, nose, malar eminences, mentum, mouth, gums, and chin in face presentation. Based on the position of the chin, face presentation can be further divided into mentum anterior, posterior, or transverse. In brow presentation, anterior fontanelle and face can be palpated except for the mouth and the chin. Brow presentation can then be further described based on the position of the anterior fontanelle as frontal anterior, posterior, or transverse.

Diagnosing the exact presentation can be challenging, and face presentation may be misdiagnosed as frank breech. To avoid any confusion, a bedside ultrasound scan can be performed. [6]  The ultrasound imaging can show a reduced angle between the occiput and the spine or, the chin is separated from the chest. However, ultrasound does not provide much predicting value in the outcome of the labor. [7]

• Anatomy and Physiology

Before discussing the mechanism of labor in the face or brow presentation, it is crucial to highlight some anatomical landmarks and their measurements. 

Planes and Diameters of the Pelvis

The three most important planes in the female pelvis are the pelvic inlet, mid pelvis, and pelvic outlet. 

Four diameters can describe the pelvic inlet: anteroposterior, transverse, and two obliques. Furthermore, based on the different landmarks on the pelvic inlet, there are three different anteroposterior diameters, named conjugates: true conjugate, obstetrical conjugate, and diagonal conjugate. Only the latter can be measured directly during the obstetric examination. The shortest of these three diameters is obstetrical conjugate, which measures approximately 10.5 cm and is a distance between the sacral promontory and 1 cm below the upper border of the symphysis pubis. This measurement is clinically significant as the fetal head must pass through this diameter during the engagement phase. The transverse diameter measures about 13.5cm and is the widest distance between the innominate line on both sides. 

The shortest distance in the mid pelvis is the interspinous diameter and usually is only about 10 cm. 

Fetal Skull Diameters

There are six distinguished longitudinal fetal skull diameters:

• Suboccipito-bregmatic: from the center of anterior fontanelle (bregma) to the occipital protuberance, measuring 9.5 cm. This is the presenting diameter in vertex presentation. 
• Suboccipito-frontal: from the anterior part of bregma to the occipital protuberance, measuring 10 cm 
• Occipito-frontal: from the root of the nose to the most prominent part of the occiput, measuring 11.5cm
• Submento-bregmatic: from the center of the bregma to the angle of the mandible, measuring 9.5 cm. This is the presenting diameter in face presentation where the neck is hyperextended. 
• Submento-vertical: from the midpoint between fontanelles and the angle of the mandible, measuring 11.5cm 
• Occipito-mental: from the midpoint between fontanelles and the tip of the chin, measuring 13.5 cm. It is the presenting diameter in brow presentation. 

Cardinal Movements of Normal Labor

• Neck flexion
• Internal rotation
• Extension (delivers head)
• External rotation (Restitution)
• Expulsion (delivery of anterior and posterior shoulders)

Some of the key movements are not possible in the face or brow presentations.  

Based on the information provided above, it is obvious that labor will be arrested in brow presentation unless it spontaneously changes to face or vertex, as the occipito-mental diameter of the fetal head is significantly wider than the smallest diameter of the female pelvis. Face presentation can, however, be delivered vaginally, and further mechanisms of face delivery will be explained in later sections.

• Indications

As mentioned previously, spontaneous vaginal delivery can be successful in face presentation. However, the main indication for vaginal delivery in such circumstances would be a maternal choice. It is crucial to have a thorough conversation with a mother, explaining the risks and benefits of vaginal delivery with face presentation and a cesarean section. Informed consent and creating a rapport with the mother is an essential aspect of safe and successful labor.

• Contraindications

Vaginal delivery of face presentation is contraindicated if the mentum is lying posteriorly or is in a transverse position. In such a scenario, the fetal brow is pressing against the maternal symphysis pubis, and the short fetal neck, which is already maximally extended, cannot span the surface of the maternal sacrum. In this position, the diameter of the head is larger than the maternal pelvis, and it cannot descend through the birth canal. Therefore the cesarean section is recommended as the safest mode of delivery for mentum posterior face presentations. 

Attempts to manually convert face presentation to vertex, manual or forceps rotation of the persistent posterior chin to anterior are contraindicated as they can be dangerous.

Persistent brow presentation itself is a contraindication for vaginal delivery unless the fetus is significantly small or the maternal pelvis is large.

Continuous electronic fetal heart rate monitoring is recommended for face and brow presentations, as heart rate abnormalities are common in these scenarios. One study found that only 14% of the cases with face presentation had no abnormal traces on the cardiotocograph. [8] It is advised to use external transducer devices to prevent damage to the eyes. When internal monitoring is inevitable, it is suggested to place monitoring devices on bony parts carefully. 

People who are usually involved in the delivery of face/ brow presentation are:

• Experienced midwife, preferably looking after laboring woman 1:1
• Senior obstetrician 
• Neonatal team - in case of need for resuscitation 
• Anesthetic team - to provide necessary pain control (e.g., epidural)
• Theatre team  - in case of failure to progress and an emergency cesarean section will be required.
• Preparation

No specific preparation is required for face or brow presentation. However, it is essential to discuss the labor options with the mother and birthing partner and inform members of the neonatal, anesthetic, and theatre co-ordinating teams.

• Technique or Treatment

Mechanism of Labor in Face Presentation

During contractions, the pressure exerted by the fundus of the uterus on the fetus and pressure of amniotic fluid initiate descent. During this descent, the fetal neck extends instead of flexing. The internal rotation determines the outcome of delivery, if the fetal chin rotates posteriorly, vaginal delivery would not be possible, and cesarean section is permitted. The approach towards mentum-posterior delivery should be individualized, as the cases are rare. Expectant management is acceptable in multiparous women with small fetuses, as a spontaneous mentum-anterior rotation can occur. However, there should be a low threshold for cesarean section in primigravida women or women with large fetuses.

When the fetal chin is rotated towards maternal symphysis pubis as described as mentum-anterior; in these cases further descend through the vaginal canal continues with approximately 73% cases deliver spontaneously. [9] Fetal mentum presses on the maternal symphysis pubis, and the head is delivered by flexion. The occiput is pointing towards the maternal back, and external rotation happens. Shoulders are delivered in the same manner as in vertex delivery.

Mechanism of Labor in Brow Presentation

As this presentation is considered unstable, it is usually converted into a face or an occiput presentation. Due to the cephalic diameter being wider than the maternal pelvis, the fetal head cannot engage; thus, brow delivery cannot take place. Unless the fetus is small or the pelvis is very wide, the prognosis for vaginal delivery is poor. With persistent brow presentation, a cesarean section is required for safe delivery.

• Complications

As the cesarean section is becoming a more accessible mode of delivery in malpresentations, the incidence of maternal and fetal morbidity and mortality during face presentation has dropped significantly. [10]

However, there are still some complications associated with the nature of labor in face presentation. Due to the fetal head position, it is more challenging for the head to engage in the birth canal and descend, resulting in prolonged labor.

Prolonged labor itself can provoke foetal distress and arrhythmias. If the labor arrests or signs of fetal distress appear on CTG, the recommended next step in management is an emergency cesarean section, which in itself carries a myriad of operative and post-operative complications.

Finally, due to the nature of the fetal position and prolonged duration of labor in face presentation, neonates develop significant edema of the skull and face. Swelling of the fetal airway may also be present, resulting in respiratory distress after birth and possible intubation.

• Clinical Significance

During vertex presentation, the fetal head flexes, bringing the chin to the chest, forming the smallest possible fetal head diameter, measuring approximately 9.5cm. With face and brow presentation, the neck hyperextends, resulting in greater cephalic diameters. As a result, the fetal head will engage later, and labor will progress more slowly. Failure to progress in labor is also more common in both presentations compared to vertex presentation.

Furthermore, when the fetal chin is in a posterior position, this prevents further flexion of the fetal neck, as browns are pressing on the symphysis pubis. As a result, descend through the birth canal is impossible. Such presentation is considered undeliverable vaginally and requires an emergency cesarean section.

Manual attempts to change face presentation to vertex, manual or forceps rotation to mentum anterior are considered dangerous and are discouraged.

• Enhancing Healthcare Team Outcomes

A multidisciplinary team of healthcare experts supports the woman and her child during labor and the perinatal period. For a face or brow presentation to be appropriately diagnosed, an experienced midwife and obstetrician must be involved in the vaginal examination and labor monitoring. As fetal anomalies, such as anencephaly or goiter, can contribute to face presentation, sonographers experienced in antenatal scanning should also be involved in the care. It is advised to inform the anesthetic and neonatal teams in advance of the possible need for emergency cesarean section and resuscitation of the neonate. [11] [12]

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Disclosure: Julija Makajeva declares no relevant financial relationships with ineligible companies.

Disclosure: Mohsina Ashraf declares no relevant financial relationships with ineligible companies.

This book is distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ), which permits others to distribute the work, provided that the article is not altered or used commercially. You are not required to obtain permission to distribute this article, provided that you credit the author and journal.

• Cite this Page Makajeva J, Ashraf M. Delivery, Face and Brow Presentation. [Updated 2023 Jan 9]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-.

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• Sonographic diagnosis of fetal head deflexion and the risk of cesarean delivery. [Am J Obstet Gynecol MFM. 2020] Sonographic diagnosis of fetal head deflexion and the risk of cesarean delivery. Bellussi F, Livi A, Cataneo I, Salsi G, Lenzi J, Pilu G. Am J Obstet Gynecol MFM. 2020 Nov; 2(4):100217. Epub 2020 Aug 18.
• Review Sonographic evaluation of the fetal head position and attitude during labor. [Am J Obstet Gynecol. 2022] Review Sonographic evaluation of the fetal head position and attitude during labor. Ghi T, Dall'Asta A. Am J Obstet Gynecol. 2022 Jul 6; . Epub 2022 Jul 6.
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Fetal Positions for Labor and Birth

Knowing your baby's position can you help ease pain and speed up labor

In the last weeks of pregnancy , determining your baby's position can help you manage pain and discomfort. Knowing your baby's position during early labor can help you adjust your own position during labor and possibly even speed up the process.

Right or Left Occiput Anterior

Illustration by JR Bee, Verywell 

Looking at where the baby's head is in the birth canal helps determine the fetal position.The front of a baby's head is referred to as the anterior portion and the back is the posterior portion. There are two different positions called occiput anterior (OA) positions that may occur.

The left occiput anterior (LOA) position is the most common in labor. In this position, the baby's head is slightly off-center in the pelvis with the back of the head toward the mother's left thigh.

The right occiput anterior (ROA) presentation is also common in labor. In this position, the back of the baby is slightly off-center in the pelvis with the back of the head toward the mother's right thigh.

In general, OA positions do not lead to problems or additional pain during labor or birth.  

Right or Left Occiput Transverse

Illustration by JR Bee, Verywell  

When facing out toward the mother's right thigh, the baby is said to be left occiput transverse (LOT). This position is halfway between a posterior and anterior position. If the baby was previously in a posterior position (in either direction), the LOT position indicates positive movement toward an anterior position.

When the baby is facing outward toward the mother's left thigh, the baby is said to be right occiput transverse (ROT). Like the previous presentation, ROT is halfway between a posterior and anterior position. If the baby was previously in a posterior position, ROT is a sign the baby is making a positive move toward an anterior position.

When a baby is in the left occiput transverse position (LOT) or right occiput transverse (ROT) position during labor, it may lead to more pain and a slower progression.

Tips to Reduce Discomfort

There are several labor positions a mother can try to alleviate pain and encourage the baby to continue rotating toward an anterior position, including:

• Pelvic tilts
• Standing and swaying

A doula , labor nurse, midwife , or doctor may have other suggestions for positions.

Right or Left Occiput Posterior

When facing forward, the baby is in the occiput posterior position. If the baby is facing forward and slightly to the left (looking toward the mother's right thigh) it is in the left occiput posterior (LOP) position. This presentation can lead to more back pain (sometimes referred to as " back labor ") and slow progression of labor.

In the right occiput posterior position (ROP), the baby is facing forward and slightly to the right (looking toward the mother's left thigh). This presentation may slow labor and cause more pain.

To help prevent or decrease pain during labor and encourage the baby to move into a better position for delivery, mothers can try a variety of positions, including:

• Hands and knees
• Pelvic rocking

Mothers may try other comfort measures, including:

• Bathtub or shower (water)
• Counter pressure
• Movement (swaying, dancing, sitting on a birth ball )
• Rice socks (heat packs)

How a Doctor Determines Baby's Position

Leopold's maneuvers are a series of hands-on examinations your doctor or midwife will use to help determine your baby's position. During the third trimester , the assessment will be done at most of your prenatal visits.   Knowing the baby's position before labor begins can help you prepare for labor and delivery.

Once labor begins, a nurse, doctor, or midwife will be able to get a more accurate sense of your baby's position by performing a vaginal exam. When your cervix is dilated enough, the practitioner will insert their fingers into the vagina and feel for the suture lines of the baby's skull as it moves down in the birth canal.   It's important to ensure the baby is head down and moving in the right direction.

Labor and delivery may be more complicated if the baby is not in a head-down position, such as in the case of a breech presentation.

How You Can Determine Baby's Position

While exams by health practitioners are an important part of your care, from the prenatal period through labor and delivery, often the best person to assess a baby's position in the pelvis is you. Mothers should pay close attention to how the baby moves and where different movements are felt.

A technique called belly mapping can help mothers ask questions of themselves to assess their baby's movement and get a sense of the position they are in as labor approaches.

For example, the position of your baby's legs can be determined by asking questions about the location and strength of the kicking you feel. The spots where you feel the strongest kicks are most likely where your baby's feet are.

Other landmarks you can feel for include a large, flat plane, which is most likely your baby's back. Sometimes you can feel the baby arching his or her back.

At the top or bottom of the flat plane, you may feel either a hard, round shape (most likely your baby's head) or a soft curve (most likely to be your baby's bottom).

Guittier M, Othenin-Girard V, de Gasquet B, Irion O, Boulvain M. Maternal positioning to correct occiput posterior fetal position during the first stage of labour: a randomised controlled trial .  BJOG: An International Journal of Obstetrics & Gynaecology . 2016;123(13):2199-2207. doi:10.1111/1471-0528.13855

Gizzo S, Di Gangi S, Noventa M, Bacile V, Zambon A, Nardelli G. Women’s Choice of Positions during Labour: Return to the Past or a Modern Way to Give Birth? A Cohort Study in Italy .  Biomed Res Int . 2014;2014:1-7. doi:10.1155/2014/638093

Ahmad A, Webb S, Early B, Sitch A, Khan K, MacArthur C. Association between fetal position at onset of labor and mode of delivery: a prospective cohort study .  Ultrasound in Obstetrics & Gynecology . 2014;43(2):176-182. doi:10.1002/uog.13189

Nishikawa M, Sakakibara H. Effect of nursing intervention program using abdominal palpation of Leopold’s maneuvers on maternal-fetal attachment .  Reprod Health . 2013;10(1). doi:10.1186/1742-4755-10-12

Choi S, Park Y, Lee D, Ko H, Park I, Shin J. Sonographic assessment of fetal occiput position during labor for the prediction of labor dystocia and perinatal outcomes .  The Journal of Maternal-Fetal & Neonatal Medicine . 2016;29(24):3988-3992. doi:10.3109/14767058.2016.1152250

Bamberg C, Deprest J, Sindhwani N et al. Evaluating fetal head dimension changes during labor using open magnetic resonance imaging .  J Perinat Med . 2017;45(3). doi:10.1515/jpm-2016-0005

Gabbe S, Niebyl J, Simpson J et al.  Obstetrics . Philadelphia, Pa.: Elsevier; 2012.

By Robin Elise Weiss, PhD, MPH Robin Elise Weiss, PhD, MPH is a professor, author, childbirth and postpartum educator, certified doula, and lactation counselor.

Toward the end of pregnancy, the fetus moves into position for birth. Normally, the position of a fetus is facing rearward (toward the woman’s back) with the face and body angled to one side and the neck flexed, and presentation is head first.

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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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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Classification of normal and abnormal fetal heart ultrasound images and identification of ventricular septal defects based on deep learning

Affiliations.

• 1 The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian, P.R. China.
• 2 College of Engineering, Huaqiao University, Quanzhou, Fujian, P.R. China.
• 3 Collaborative Innovation Center for Maternal and Infant Health Service Application Technology, Quanzhou Medical College, Quanzhou, Fujian, P.R. China.
• PMID: 37161929
• DOI: 10.1515/jpm-2023-0041

Objectives: Congenital heart defects (CHDs) are the most common birth defects. Recently, artificial intelligence (AI) was used to assist in CHD diagnosis. No comparison has been made among the various types of algorithms that can assist in the prenatal diagnosis.

Methods: Normal and abnormal fetal ultrasound heart images, including five standard views, were collected according to the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) Practice guidelines. You Only Look Once version 5 (YOLOv5) models were trained and tested. An excellent model was screened out after comparing YOLOv5 with other classic detection methods.

Results: On the training set, YOLOv5n performed slightly better than the others. On the validation set, YOLOv5n attained the highest overall accuracy (90.67 %). On the CHD test set, YOLOv5n, which only needed 0.007 s to recognize each image, had the highest overall accuracy (82.93 %), and YOLOv5l achieved the best accuracy on the abnormal dataset (71.93 %). On the VSD test set, YOLOv5l had the best performance, with a 92.79 % overall accuracy rate and 92.59 % accuracy on the abnormal dataset. The YOLOv5 models achieved better performance than the Fast region-based convolutional neural network (RCNN) & ResNet50 model and the Fast RCNN & MobileNetv2 model on the CHD test set (p<0.05) and VSD test set (p<0.01).

Conclusions: YOLOv5 models are able to accurately distinguish normal and abnormal fetal heart ultrasound images, especially with respect to the identification of VSD, which have the potential to assist ultrasound in prenatal diagnosis.

Keywords: congenital heart defect; deep learning; prenatal diagnosis.

© 2023 Walter de Gruyter GmbH, Berlin/Boston.

• Artificial Intelligence
• Deep Learning*
• Fetal Heart / diagnostic imaging
• Heart Defects, Congenital* / diagnosis
• Heart Septal Defects, Ventricular* / diagnostic imaging
• Ultrasonography, Prenatal / methods

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May 14, 2024

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Fetal cells can be traced back to the first day of embryonic development

by Lori Dajose, California Institute of Technology

Though more than 8 million babies have been born through in vitro fertilization (IVF), 70% of IVF implantations fail. As IVF is becoming a more common route to pregnancy in cases of infertility, there is a need for better understanding of embryonic development at this early stage.

Researchers in the laboratory of Caltech's Magdalena Zernicka-Goetz, Bren Professor of Biology and Biological Engineering, study the biological processes underlying the earliest days of human development.

Now, a new study from the Zernicka-Goetz lab demonstrates that when human embryos are composed of two cells, at just 1 day old, only one of these cells will create most of the fetal body cells in addition to placental cells, while the other will only create placental cells.

The research changes the long-standing paradigm that the two cells at this stage both contribute equally to all parts of the developing embryo, suggesting that "specification"—the phenomenon of cells having specific individual roles—happens much earlier in development than previously believed.

The findings have implications for how embryos intended for IVF implantation are assessed for abnormalities.

"Often, in an IVF clinic, a few placental cells from the outside of the 6-day-old embryo will be selected for a genetic diagnosis to determine if they have chromosomal abnormalities ," says Zernicka-Goetz.

"Our results show that, by extrapolation, those outside cells chosen are unlikely to be contributing to the fetal body. The genetic information from those cells may not be as informative as sampling the fetal cells themselves."

A paper describing the research was published on May 13 in the journal Cell .

The 1-day-old human embryo is composed of just two cells, each called a blastomere. Using embryos donated for research by IVF clinics, the team labeled blastomeres with a colored dye, then used time-lapse imaging to watch as the cells divided over the course of six days.

New cells carried the same color dye as their parent cell. Through this process, the team determined that fetal body cells exclusively originated from a single blastomere, while placental cells came from both.

"In addition to being valuable information for improving IVF, our study is part of a large body of research into evolutionary processes within the body," says postdoctoral scholar Sergi Junyent, a co-first author on the new paper.

"Studying how different cell lineages populate from original cells has implications for understanding what happens after mutations, how they lead to cancer, and so on."

Journal information: Cell

Provided by California Institute of Technology

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