Vaginal Birth After Cesarean (VBAC)
Vaginal birth after cesarean (VBAC) has become a hotly contested topic. VBACs were once encouraged across the board. Recently, however, there have been concerns about VBAC due to highly publicized cases of uterine rupture and serious injury to both mother and baby. Because a VBAC requires an anesthesiologist to be at the ready continuously in case an emergency C-section is needed, there has been a dampening of the initial enthusiasm for the procedure, especially in level-one (low-risk) obstetrical hospitals.
The recent trend toward patient-choice C-sections also shows a declining enthusiasm on the part of many women for vaginal delivery in general, VBAC or otherwise. There has never been a randomized controlled clinical study trial comparing VBAC with repeat C-section, and it is unlikely that one will ever be done.
In deciding if you'd like to try a VBAC, you need to discuss the reason for your first C-section with your health-care provider. If you had a C-section previously for failure to progress in labor and this current baby seems to be about the same size, it's unlikely you will be successful with a VBAC.
But a prior C-section because of breech position does not make it likely a VBAC would be unsuccessful. The most serious risk associated with VBAC is rupture of the scar from the previous C-section.
VBACs are drastically declining because of studies indicating they are not as safe as was once believed. The VBAC rate is down 67 percent since 1996 and made up only 9.2 percent of all 2004 births.
A study in the American Journal of Obstetrics and Gynecology found that the older a woman is, the less likely it is she will be able to successfully have a vaginal birth after a previous C-section. Among all women, about 20 to 40 percent of VBACs are unsuccessful. Those most successful with VBAC shared the following characteristics:
Had a low-segment transverse incision with their prior section
Have a normal-sized baby who is not in breech
Have a pelvis large enough for the baby to fit through
Spontaneously go into labor (are not induced)
Have not had a C-section in the last two years
Have not had a C-section due to a large-for-gestational-age baby
A trial of labor to see if you can progress might be something to consider, but studies show that C-sections done after failed trials of labor have higher complications than C-sections performed without any attempt at labor (that is, a scheduled C-section). You have the right to change your mind at any time during a trial of VBAC, regardless of your reasons.
In deciding whether to do a VBAC, you need to weigh the risks. A repeat C-section carries the risk of infection, a longer recovery, difficulty holding the baby, as well as all the risks of surgery, such as blood clots. A VBAC carries the risk of uterine rupture and the risk of being unsuccessful, leading to a C-section after hours of labor, which may have a higher complication rate than if it had been performed electively.
If you are induced for your VBAC, you may be at a higher risk of complications. Several recent studies have shown that the use of prostaglandin analogues for cervical ripening is associated with a higher incidence of uterine rupture for VBACs. Although Pitocin alone did not appear to increase the risk of uterine rupture, many obstetricians will no longer induce a patient with a prior C-section who wants a VBAC. However, Pitocin augmentation during labor appears to be safe in skilled hands.