What to Know About Vaginal Birth After a C-Section (VBAC)

Many parents who've experienced a C-section hope to avoid the procedure again in subsequent pregnancies. Due to the increased possibility of uterine rupture, a vaginal birth after cesarean (VBAC) is sometimes considered high-risk by doctors—but most people have a VBAC without any complications.

"A VBAC is a safe option for many women who have had one [or sometimes two] previous C-section and who have been identified as low risk—and that's the majority of women," says Nancy Petit, MD, chief of the division of obstetrics at St. Francis Hospital in Wilmington, Delaware.

So what's the difference between a VBAC and a C-section, and how can you decide what's right for you? Read these important facts, and discuss your concerns with your health care provider.

Benefits of VBAC Birth

People might want a vaginal birth after a C-section for several reasons, including the following:

• Desire to experience a vaginal birth
• Elimination of the need for abdominal surgery, which has inherent risks like infection, hemorrhage, and anesthesia-related complications
• Reduction of the risk for possible blood transfusions
• Decreased length of hospital stay
• Shorter recovery time
• Avoidance of health problems associated with multiple C-section deliveries (hysterectomy, bowel or bladder injury, placenta problems in future pregnancies, etc.)

According to a Cochran Review of data, there appears to be no statistical difference in "death or serious morbidity" from planned C-sections and VBACs, meaning they may each carry the same risks and benefits. Still, your health care provider can inform you about your specific scenario.

VBAC Risks and Uterine Rupture

Along with the benefits of vaginal birth after cesarean, there are also a handful of risks. In rare cases, VBAC can lead to uterine rupture, a dangerous tearing of the uterine muscle or a past C-section scar.

"Uterine rupture can be catastrophic for the baby and may be life-threatening to the mother," says Marilynn Frederiksen, MD, an associate professor of clinical obstetrics and gynecology at the Feinberg Medical School of Northwestern University and a member of a panel of childbirth experts convened by the NIH.

If a uterine rupture results in excessive bleeding, a patient may have to undergo a blood transfusion or an emergency hysterectomy, explains William Grobman, MD, associate professor of obstetrics and gynecology at Northwestern University's Feinberg School of Medicine, in Chicago. That said, the incidence of uterine rupture is low—less than 1 %—and it's riskier if you need to be induced.

According to the American College of Obstetricians and Gynecologists (ACOG), other risks of VBAC include infection and blood loss. There's also a chance the VBAC will fail, leading to an emergency C-section.

Do All Hospitals Offer Vaginal Birth After C-Section?

Some OB-GYNs no longer offer VBACs, and some hospitals offer it only with strict stipulations, such as going into labor spontaneously before your due date. (A VBAC should never be attempted if labor has been induced.) VBACs should only take place in hospitals that can provide emergency life-saving care if necessary.

Fear of litigation drives much of the reluctance to allow VBACs. "Lots of providers and hospitals refuse to offer women the option because they fear getting sued if something goes wrong," says Amy Romano, CNM, a nurse-midwife in Connecticut and author of Lamaze International's Science & Sensibility blog. Even some midwives have stopped offering VBACs because of liability issues.

Budget cuts and lack of funding may prevent some hospitals from having the necessary personnel for a VBAC.

Is VBAC Delivery Right For Me?

Before determining whether you can attempt a VBAC, your doctor will carefully consider your case. One important factor: the reasoning behind your previous C-section. If it resulted from something that isn't likely to occur again, such as a breech baby, your chances of being able to attempt a VBAC are higher than if your C-section was due to an issue that could reemerge, such as not dilating.

Ultimately, it's up to your physician to decide what's right for you. VBAC tends to be safest for those who:

• Have had at least one vaginal delivery. If you've given birth multiple times, but only one instance was a VBAC, you have a lower risk for uterine rupture, says Brian Mercer, MD, professor of obstetrics and gynecology at Case Western Reserve University School of Medicine in Cleveland. Why? "Your body has demonstrated that it can complete labor," says Dr. Mercer. Therefore you're more likely to be able to do it again.
• Have had one or two previous C-sections. The risk of uterine rupture increases with each C-section performed; most doctors will perform VBACs on people who had up to two prior C-sections.
  
• Had a low-transverse incision—a horizontal cut low in the uterus—during their previous C-section. If you had a high vertical or "classical" cesarean, made by cutting vertically in the upper uterus, your risk of uterine rupture is greater.
  
• Have a history of low-risk pregnancies.
• Are delivering a baby who is a reasonable size.
• Do not have certain health conditions, including high blood pressure, diabetes (pre-existing or gestational), or active genital herpes.
• Have no history of uterine surgery or other uterine problems.
• Gave birth at least 18 months prior, which allows the body can properly heal
• Don't have placenta previa (low-lying placenta) or placental abruption.
  
• Are younger than 35, though doctors aren't sure why older patients have a lower chance of having a successful VBAC than younger ones. There are many theories about this, says David Stamilio, MD, associate professor of obstetrics and gynecology at Washington University School of Medicine in St. Louis: "It could be that as women age, they tend to have larger babies, or their muscles are not as conditioned. No one really knows."
• Maintain a healthy weight during pregnancy. If you were slim when you became pregnant and haven't gained much weight since then, your chances of a problem-free VBAC are higher. "Being overweight doesn't rule one out, but the increase of soft tissue around the pelvis may make it harder for a baby to come through the birth canal," says Dr. Mercer.
• Want more kids. Having more than two cesareans may be riskier than attempting a VBAC, as the chance of surgical complications increases with the number of C-sections a person has. The most serious risk: placenta accreta, where the placenta abnormally adheres to the lining of the uterus. This can lead to uncontrollable bleeding and might require a hysterectomy.

When determining if you're a candidate for vaginal birth after cesarean, your doctor will also consider the baby's size relative to the size of your pelvis. If the baby can't fit, your uterus may be subject to prolonged stress in a delivery that won't progress properly.

Also, there may be factors that could signal possible complications during the baby's delivery (for example, breech presentation), which might make VBAC too risky when coupled with the other risk factors of prior C-section. In the long run, most of these factors can be identified prior to the delivery. So you should be able to discuss your options at length with your health care provider.

Preparing for a Vaginal Birth After C-Section

If you want to try a vaginal birth after a C-section and are a good candidate, start researching your options early in pregnancy. If your doctor or hospital doesn't allow VBACs, consider other providers. For example, a major medical center with a level-3 NICU (neonatal intensive-care unit) and round-the-clock staffing by anesthesiologists is more likely to offer the option than a small community hospital.

Also, follow the experts' advice: Take childbirth classes that address vaginal birth after C-section, and read as much about the process as possible.

Support and information can come from childbirth educators, doulas, midwives, and people online and in other communities who have had a VBAC. "Making a choice that is not considered mainstream, even when research supports its safety, can be very difficult," says nurse-midwife Romano. "So the more support a woman has, the better."

Regardless of your approach, focus on the fundamental goal. Iffath Hoskins, MD, chair of obstetrics and gynecology at Lutheran Medical Center in Brooklyn, New York, reminds all her VBAC patients about what really matters: "A successful birth means a healthy [parent] and a healthy baby, regardless of the route of delivery."