Understanding External Cephalic Version (ECV) for Breech Babies

Late in the last trimester of pregnancy, a developing fetus should ideally be in a head-down position ("vertex" presentation), so they'll be born head first, but that's not always the case. According to the American College of Obstetricians and Gynecologists (ACOG), about 3% to 4% of babies during this stage present as breech, meaning the bum or feet are closest to the cervix.

Vaginal delivery of a breech baby can be dangerous because newborns' heads are typically wider than their bodies. Therefore, when a baby is born feet first, their body may not stretch the cervix enough, and the baby's head or shoulders could get stuck inside the birth canal.

Another potential complication is a prolapsed umbilical cord (when the cord slips down into the birth canal before the baby's body). If the umbilical cord moves into the vagina ahead of the baby, it could become pinched or pressured in a way that impedes oxygen flow.

A health care provider can assess your baby's presentation by feeling specific points of your abdomen and confirm with an ultrasound or pelvic exam. If your fetus is in breech position at 36 or 37 weeks, your health care provider might offer an external cephalic version, also known as a "version" or ECV.

Read on to learn what to expect during an ECV, the risks, and your options if ECV isn't successful.

What Is ECV?

External cephalic version (ECV) is a procedure performed around 36 or 37 weeks gestation to turn a baby from a breech or side-lying (transverse) position to the optimal head-down position before labor.

To perform an ECV procedure, a doctor or midwife, usually with the help of another health care professional, uses their hands to apply pressure to your abdomen to guide the baby into a head-first position. Successful ECV makes it possible to attempt a vaginal birth.

What to Expect During an ECV Procedure

If you undergo an ECV for your breech baby, you may receive a mild sedative and/or low-dose spinal anesthesia before the procedure. Medications commonly used during an ECV procedure include nitrous oxide (aka "laughing gas"), terbutaline (a tocolytic used to prevent early labor), calcium channel blockers, and an epidural, says Marsha Granese, M.D., an OB-GYN with Mission Hospital in Mission Viejo, California.

"I use an epidural and a lot of abdominal lubrication and have given tocolytic (medicines that stop contractions) injections to help stop the uterus from contracting and allow for the most relaxed uterus," she says.

People who receive an epidural can expect to feel moderate to intense pressure. Dr. Granese says that without an epidural, you can expect extreme pressure, pain, and short-windedness.

Both you and your fetus are monitored throughout the procedure, and ECV is stopped immediately if any signs of fetal distress occur. It may take several attempts using ultrasound to guide their turns to perform a successful version.

ECV Benefits and Risks

The main benefit of ECV is that, when successful, it allows for a safer birth. When a fetus is not in a head-down position, vaginal birth is riskier and, in some instances, may not be an option. In addition, while a C-section is preferred for a breech presentation, surgical birth carries its own risks.

However, not every breech pregnancy is eligible for a version. For example, a 2013 review published in Acta Obstetricia et Gynecologica Scandinavica lists 39 contraindications. However, many of those contraindications depend on your health care provider's experience level and your overall health and circumstance.

According to ACOG, some of the contraindications, or scenarios when doctors wouldn't perform ECV, include:

• You are carrying multiples
• There are concerns about your baby's health
• You have reproductive abnormalities
• The placenta is in a risky place
• You are at risk for placental abruption

Risks associated with ECV include placental separation (abruption), internal bleeding, rupture of membranes, fetal distress, and preterm labor. Doctors usually perform ECV near a delivery room, so if problems arise, they can perform a C-section quickly.

There's also the possibility that ECV won't work: The overall success rate for ECV procedures is 58%. And even if the version does work, there's a chance your baby could return to the breech position before labor begins.

What If ECV Isn't Successful?

If your ECV isn't successful and your baby remains in the breech position, there are alternative methods that can help encourage your baby to turn. For example, Dr. Granese recommends considering acupuncture with moxibustion (burning dried mugwort at select points of the body). Another option is a chiropractic adjustment, called the Webster technique, which balances the pelvic muscles to allow the fetus to move easier.

However, Dr. Granese doesn't want parents to feel disappointed if ECV fails. "Statistics say the baby is far safer during cesarean delivery than in a vaginal breech delivery," says Dr. Ganese. According to a 2015 Cochrane review, planned cesareans for breech babies resulted in fewer fetal deaths and injuries than vaginal births.

That said, some people may be able to attempt a vaginal breech delivery. Whether that's an option in your situation largely depends on your risk factors and whether your health care provider has experience with vaginal breech birth.

And if you have a C-section, you may still be able to have a vaginal birth with your next pregnancy (known as a vaginal birth after cesarean or VBAC). That's especially true if the reason for your first cesarean was because of a breech presentation.