Vaginal Breech Delivery: Is It Safe?

Only three percent of unborn babies are not in a head-down position when they reach term. For these breech babies, cesarean section has become the preferred mode of delivery in most countries. Parents who are expecting a breech baby may face a dilemma — is a cesarean inevitable or may a vaginal delivery be attempted?

Here, we explore the risks of breech birth and look at the most favorable circumstances for a vaginal breech birth.

What is breech presentation?

The normal position for delivery is called vertex presentation. In this position, the baby's head faces the cervix so that the head will be the first part to be born. A fetus with its head in the upper part of the uterus and its buttocks in the lower part — closer to the cervix — is in a breech position.

Breech positions are quite common during the earlier stages of pregnancy:

• at 32 weeks of pregnancy, 25% of babies will be in a breech position.
• by term (38-42 weeks), this will have dropped to 3%.

There are four different variations of the breech position:

• Frank breech. The baby's buttocks face the mother's cervix, while the legs are folded upward, with the feet next to the baby's head.

• Footling breech. The baby's feet face the mother's cervix.

• Complete breech. The baby's legs are bent and close to the buttocks, in a position that looks like sitting. Both buttocks and legs face the cervix.

• Kneeling breech. This is so rare that most people will not have heard about it. One leg is stretched upward as with the frank breech position, while the other leg appears next to the buttocks as with the complete breech position.

What causes breech presentation?

It is impossible to make blanket statements about this, but there are risk factors that should be considered. During the earlier stages of pregnancy, most babies assume a breech position only to move into the head-down position before birth. It is highly likely to prematurity is the sole cause of breech presentation in most cases, yet the fact remains that a small minority of term babies are still breech. 

Breech presentation is also more common during twin pregnancies, subsequent pregnancies (in other words, where the mother has already given birth before), and where the mother suffers from uterine fibroids or uterine malformations. In addition, the placental complication placenta previa where the placenta covers the cervix is associated with a higher chance of breech presentation. Too little or too much amniotic fluid are other risk factors. Finally, babies with birth defects are more likely to be breech.

What Is The Big Deal With Vaginal Breech Birth?

A breech presentation during the third trimester of pregnancy provokes many questions — for both doctors and parents — that all need answers. Should there be an attempt to turn the baby into a vertex position? If the baby remains breech, should be mother have a cesarean section? Would it be safe to attempt a vaginal delivery?

Expectant parents who are facing these questions will probably wonder what the “big deal” is with a breech baby at some point; a question that is sadly rarely discussed. You'll hear that breech deliveries pose more of a risk to the baby than vertex deliveries. But why is this the case?

First, let's take a look at what happens during a normal, head-down labor and birth. During a vertex vaginal labor, contractions will gradually push the baby toward the cervix while the cervix is also dilating (opening). The head then leads the way out, and the rest of the body effortlessly follows down the already dilated and stretched path.

Your typical breech vaginal birth is not that straightforward, for many reasons. The baby's position results in enormous pressure on its hips during the descent into the birth canal, and many breech babies born vaginally emerge with a bruised hip and swollen genitals.

The next big risk, head entrapment, is a particular concern in premature babies. The baby's buttocks and head are the same size in a term baby, which means that the cervix will dilate enough for the head to emerge. A premature baby's head is, on the other hand, larger than its buttocks. Once the baby's body is out, the cervix may not be dilated enough to accommodate the head, which is then trapped in the uterus. Yes, this is as dangerous as it sounds — head entrapment can easily be fatal, especially no highly skilled and experienced professionals present. (In other words, do not attempt a home birth with a breech baby, even if you would prefer a vaginal delivery!)

Finally, umbilical cord prolapse is a risk during a vaginal breech birth. Cord prolapse is a complication during which the umbilical cord emerges from the vagina before the baby does. The baby's weight then puts pressure on the cord, quickly compromising the baby's oxygen supply and leading to death within minutes. The way in which a breech baby is positioned in the uterus makes cord prolapse more likely. The buttocks and legs do not form a "lid" that prevents the cord from slipping out, as a head does. 

There is, arguably, an extent of cord prolapse during every vaginal breech birth. After all, the umbilical cord is attached to the baby at the naval, a part of the body that is born before the head in breech births. As the head is born, its weight will put pressure on the umbilical cord. This the reason it is so important for the head to emerge very quickly after the body.

Breech Birth — Considering Your Options

Many healthcare providers will first suggest attempting to turn a breech baby into the vertex position. This is usually done in a procedure called an external cephalic version (ECV), which literally involves manually turning the baby head-down in a skilled maneuver.

This procedure is most likely to be successful earlier on in the pregnancy, because there is more space in the uterus and more amniotic fluid. This also unfortunately means that the baby may be able to turn back into the breech position.

If the version was unsuccessful, or the baby turned back to breech, or the parents decided not to attempt a version at all, there are two remaining options — a scheduled cesarean section or a vaginal breech birth. Due to the potential for complications during a vaginal breech delivery, cesarean section is considered a valid option in all developed, modern healthcare systems. Policy on breech vaginal birth varies throughout the western world.

Let's take a quick look at the policies in three different countries, to compare them:

• In the United States, the ACOG (American College of Obstetricians and Gynecologists) notes that a cesarean section is generally safer for a breech baby. It also states that the mode of delivery should depend on the obstetrician, who will almost always prefer a c-section due to lack of experience with vaginal breech birth. The ACOG says that vaginal twin delivery where the second baby is breech is less risky, and says that the mother should be counseled about the possible risks of vaginal singleton breech delivery. In practice, very few OBGYNs will do vaginal breech births.

• In Great Britain, the National Health Service (NHS) starts by recommending that women carrying a breech baby deliver in a hospital rather than at home. They recognize the risks associated with a vaginal breech delivery, and advise women against one in certain circumstances — like a large or small baby, a low-lying placenta, or having had a previous c-section. Yet, the healthcare system in the UK does not discourage breech birth as universally as happens in the US.

• In the Netherlands, generally perceived to have the most liberal maternity care policies, studies that show c-sections to be safer for breech babies are taken into account. Footling breech babies are always delivered by c-section. For other types of breech position, doctors in the Netherlands also look at risks associated with a c-section. The final decision is made jointly by parents and healthcare providers.

To put it simply, your options will depend on your local healthcare system to a great extent. Women who have a preference for a cesarean section will not have a problem obtaining one in any of the modern healthcare systems around the world. Vaginal breech birth may be an option for you if you meet certain requirements, depending on your location.

Medically speaking, vaginal breech birth is safest in the following circumstances:

• The mother has already had an uncomplicated vaginal delivery before, and has not had a cesarean section in the past.

• The baby is term, and not estimated to have either a large birth weight or a low birth weight — as determined by your healthcare provider.

• The baby is in a frank breech position and has already descended. Twins, which the second twin being in a breech position, is an alternative favorable factor.

• The baby's head is in a position that facilitates vaginal delivery, and the placenta is not located close to the cervix.

• The healthcare team is experienced in delivering breech babies vaginally, and the delivery takes place in an operating room so that an emergency c-section can quickly be carried out if necessary.

Good luck with making your decision. Do not hesitate to seek a second opinion or to specifically seek out doctors who have experience with breech deliveries, if you would prefer to have a vaginal birth. But also be flexible and prepare for a cesarean section.