During the last three days, I spent many hours riveted to my computer, watching the NIH Consensus Development Conference on VBAC in Bethesda, Maryland. Overall, the news is good. To quote from the conclusion of the final report, “Given the available evidence, TOL [trial of labor] is a reasonable option for many pregnant women with a prior low transverse uterine incision.” The panel recommends that the American College of Anesthesiologists (ACOG) and the American Society of Anesthesiologists “reassess” the ‘immediately available” requirement for physicians and anesthesia in light of strong evidence that VBAC is no more risky than labor for a first-time mother. They also recommend that “hospitals, maternity care providers, healthcare and professional liability insurers, consumers, and policymakers collaborate on the development of integrated services that could mitigate or even eliminate barriers to TOL.”
But it is clear that there is not consensus on the subject of VBAC. A practicing OB from Dallas, TX told a chilling story about an uterine rupture which resulted in brain damage for the baby in a gravida 3, para 2 mother who had had one prior vaginal delivery (supposedly a good candidate for VBAC). He said that the physician involved blamed himself for the boy’s disabilities for not stressing enough the risks of VBAC to the mother. One was left with the impression that a scarred uterus could rupture at any time during labor, leading to the unpreventable death or profound disability of the baby.
But wait! Although we cannot reduce all risk for any pregnant woman and her baby, there was compelling evidence presented at the conference that VBAC can be done safely. Although this study was not discussed during the conference, in an article published in 2001 in the American Journal of Obstetrics and Gynecology, researchers performed a retrospective chart review of all cases of uterine rupture at the University of California, San Francisco Moffett-Long Hospital over a 20 year period from 1976 to 1998. During the study period there were 38,027 deliveries and 3319 women with prior Cesareans. The attempted VBAC rate was 61.3%, of which 65.3% were successful. There were 21 cases of uterine rupture for a rate of 0.06%, but four of the ruptures were in women who did not have a history of uterine surgery or Cesarean delivery. There were no maternal deaths. There were two fetal/neonatal deaths – one was in a 25-week-old fetus whose mother presented at an outlying hospital and the second in a 25-week-old fetus with Potter’s Syndrome. None of the live-born babies had any evidence of neurologic abnormalities. Clearly, over a 20 year period, VBAC (and even uterine rupture) was “safe” at this hospital.
There are many other published studies of excellent outcomes with VBAC. But equally important, there are many published studies detailing the increased risks for both mothers and babies with Cesarean deliveries. The NIH panel concluded that there is a high grade of evidence that maternal mortality is increased with ERCD (elective repeat Cesarean delivery) over TOL. Indeed, as the Cesarean rate has soared in the USA, the maternal mortality rate may be increasing. The Joint Commission recently issue a Sentinel Alert on preventing maternal death. They note that two of the most common preventable errors are failure to pay attention to vital signs following Cesarean section and hemorrhage following Cesarean section. ABC News has reported that the maternal mortality rate in California has almost tripled over the last decade from 5.6 deaths per 100,000 to 16.9 per 100,000 in 2006, based on a report commissioned by the California Department of Health. Also concerning is the recent increase in rare but catastrophic complications associated with Cesarean delivery such as placenta accreta and cesarean scar ectopic pregnancy.
The bottom line is that pregnancy and birth are not without risk for any mother and baby. The risk of a uterine rupture in a VBAC mother is about the same as the risks of placenta abruptio or cord prolapse in a primigravida woman. Sadly, we will sometimes (but rarely) lose mothers and babies during pregnancy and childbirth. But once a woman has had a Cesarean delivery, she and her baby are at increased risk no matter whether she gives birth vaginally or via elective Cesarean. The evidence is clear that most women with a prior Cesarean section (and probably most women with more than one Cesarean) can have safe and successful VBACs. The NIH panel was clear that barriers to VBAC should be removed and that women who want to have a VBAC should be able to do so. Now it is up to maternity care providers, hospitals, insurers, and legislators [tort reform] to make it happen.
