Increasing the Odds for Success With VBAC
VBAC: Should We or Shouldn't We?
The surgical approach to infant delivery is not new. Indeed, a variety of approaches have been used to extract fetuses from the uterus when, for various reasons, a vaginal delivery is not possible.
The old notion that “once a cesarean section, always a cesarean section,” moreover, has been a dogma that has existed in obstetrics and medicine for decades. Although this has worked well, many a time, for the convenience of the mother or the physician, it is also problematic. Over time, multiple repeat cesarean sections can pose a hazard, either because the scar becomes weak and at risk of rupture or because the surgical intervention becomes very challenging.
Concerns about possible rupture with repeat cesarean sections were particularly acute in the early years before it was appreciated that there was a difference between a vertical uterine incision and a transverse uterine incision. Following the realization that the lower uterine segment is less prone to active contraction and therefore less likely to rupture, transverse uterine incisions were encouraged in virtually all circumstances, and rupture of the uterus with repeat cesarean section became less of an issue.
In more recent times, reports of trials of labor following prior cesarean delivery resulting in successful vaginal delivery began to appear, and the notion of vaginal birth after cesarean (VBAC) took off, with a wave of success, across the country and indeed around the world. However, as the number of vaginal deliveries after cesarean sections increased, the rate of uterine rupture increased as well.
The rate of uterine rupture has remained low. Still, no matter when it occurs, uterine rupture is always a challenge—a challenge to the surgeon, a problem for the mother or baby, and unfortunately, sometimes a cause of litigation. Because of this complicating set of circumstances, the issue of advisability of VBAC has become a real medical dilemma.
Should we do them? Or should we not? If we should, when should we do them? Are there any guidelines? These are just some of the questions that have arisen over the years that we have had to grapple with. It is in this light that a Master Class to address these issues seemed appropriate. We have invited Dr. George A. Macones, an expert in maternal-fetal medicine who has studied VBAC for many years, to serve as our guest author.
Dr. Macones is the Mitchell and Elaine Yanow Professor and chair of the department of obstetrics and gynecology at Washington University in St. Louis. He recently was invited to speak at a National Institutes of Health consensus development conference on VBAC. In this column, he offers us some insight into why VBAC is a reasonable option for many women, how we can select candidates and counsel our patients, and what we can do to effectively manage our patients' attempts to achieve vaginal delivery after cesarean.
