Vaginal birth after caesarean (VBAC) refers to the practice of delivering a baby vaginally after a previous baby has been delivered through caesarean section (surgically). According to the American Pregnancy Association, 90% of women who have undergone cesarean deliveries are candidates for VBAC. Approximately 60-80% of women opting for VBAC will successfully give birth vaginally, which is comparable to the overall vaginal delivery rate in the United States in 2010.

Although cesarean sections made up only 5% of all deliveries in the early 1970s, among women who did have primary cesarean sections, the century-old opinion held, "Once a caesarean, always a caesarean." A mother-driven movement supporting VBAC changed standard medical practice, and rates of VBAC rose in the 1980s and early 1990s. A major turning point occurred in 1996 when one well publicized study in the New England Journal of Medicine reported that vaginal delivery after previous caesarean section resulted in more maternal complications than did repeat cesarean delivery. The American College of Obstetrics and Gynecology subsequently issued guidelines which identified VBAC as a high-risk delivery requiring the availability of an anesthesiologist, an obstetrician, and an operating room on standby (Int J Gyn Obs; 1999; vol 66, p197). Logistical and legal (professional liability) concerns led many hospitals to enact overt or de facto VBAC bans. As a result, the rate at which VBAC was attempted fell from 26% in the early 1990s to less than 10% today.