VBAC: Insight from a Mayo Clinic specialistWonder if you're a good candidate for VBAC?
If the benefits of VBAC outweigh the risks? The answer may be up to you. Here's help weighing the pros and cons.By Mayo Clinic staffRoger Harms, M.D.
Years ago, a C-section ended any hope of future vaginal deliveries. Today, however, many women are candidates for vaginal birth after C-section (VBAC). Still, the choice to pursue VBAC or schedule a repeat C-section can be tough. Here's insight from Roger Harms, M.D., an obstetrician at Mayo Clinic, Rochester, Minn., and medical editor-in-chief of MayoClinic.com.
Why would a woman consider VBAC?The risks associated with a vaginal delivery are lower than the risks associated with a C-section overall — as long as you can deliver the baby at a facility equipped to handle a C-section in case of emergency — and the recovery time is faster. VBAC may also be appealing if you have an emotional investment in a vaginal delivery or a desire to experience natural childbirth.
It's also important to consider future pregnancies. If you've had one C-section and you're certain this is your last delivery, the difference in risk between VBAC and a second C-section is minimal. However, if you're planning more pregnancies in the future, VBAC becomes a better option with each subsequent delivery.
What are the risks of VBAC?For 20 to 40 percent of women who attempt VBAC, labor ends in a repeat C-section. This is known as a failed trial of labor after cesarean. If you must have a repeat C-section after labor has begun, you face a slightly higher risk of C-section complications, such as a uterine infection. The most concerning risk of VBAC, however, is uterine rupture — when the baby breaks through the wall of the uterus into the mother's abdominal cavity.
If your uterus ruptures, an emergency C-section is needed to prevent life-threatening complications, including heavy bleeding and infection for the mother and brain damage for the baby. In some cases, the uterus may need to be removed (hysterectomy) to stop the bleeding. If your uterus is removed, you won't be able to get pregnant again.
Can you put the risk of uterine rupture into perspective?Uterine rupture is rare, affecting fewer than 2 out of 100 women who've had a prior low transverse uterine incision — the most common type of C-section incision. Still, it's possible. And naturally, the risk of uterine rupture causes concern. If you're considering VBAC, what's important is to make sure that the facility where you'll deliver the baby is ready to deal with that complication. You'll need a surgical and anesthesia team available throughout your labor in case a C-section becomes necessary, as well as access to a blood bank.
Who's eligible for VBAC?VBAC eligibility depends on many factors. For example:
- Have you had previous vaginal deliveries? A vaginal delivery at least once before or after your prior C-section increases the odds of a successful VBAC.
- What type of uterine incision was used for the prior C-section? Scars left from certain types of incisions have an increased risk of tearing during labor and delivery.
- What prompted the prior C-section? If your prior C-section was done for a reason that isn't present during your current pregnancy — such as infection or a problem with the placenta — you may be a good candidate for VBAC.
- How many C-sections have you had? You may be a less suitable candidate for VBAC if you've had multiple C-sections.
- When was your last C-section? The risk of uterine rupture is higher if you attempt VBAC too soon after having a C-section — such as within 18 to 24 months.
- Are you delivering multiples? VBAC may be a safe option if you're delivering twins and both babies are positioned headfirst — but often repeat C-sections are recommended for twins and other multiples.
- Do you have any health conditions that might affect a vaginal delivery? If you have diabetes, heart disease, high blood pressure or active genital herpes, for example, vaginal delivery may be risky for you or your baby.
- Will you deliver the baby in a facility equipped to handle an emergency C-section? A home delivery isn't appropriate for VBAC.
How does labor and delivery during VBAC differ from labor and delivery during a routine vaginal birth?The actual physiology of labor and delivery is the same, but the precautions taken during labor are different. You and your baby will be closely monitored, and the medical team will be less tolerant of abnormal labor patterns. Your doctor will be prepared to do a repeat C-section if needed.
Some women are outspoken supporters of VBAC, while others are outspoken against it. What should a woman believe?There's always a cohort of people within the population who adopt positions with a great deal of enthusiasm and vigor, often based on their own experiences — but it isn't possible to extrapolate the experience of one person to the experience of another. If you're considering VBAC, don't be swayed by extremes. Make your decision based on the facts and your personal values and beliefs.
What other advice do you offer women who are considering VBAC?If you're considering VBAC, it's important to be flexible. You won't know what cards you'll be dealt until labor begins. The circumstances of your labor may make VBAC a clear choice, or you and your doctor may quickly decide that a repeat C-section would be best after all. If you choose an elective C-section, you'll never see what cards were in the deck — and for some women, that might be just fine.