By the beginning of the 20th century, cesarean delivery had become a relatively safe procedure. However, rupture of the uterine scar with subsequent labor was appreciated early. This danger resulted in the oft-quoted remark by Cragin (1916) that “Once a cesarean, always a cesarean.” During the intervening 50 years, enthusiasm developed to allow many of these women to be delivered vaginally. But, as chronicled next, this support has waned during the past three decades. So, as we reach the 100-year mark of Cragin’s pronouncement, the issue remains largely unsettled.
Despite Cragin’s early philosophy, some practitioners did allow labor in a subsequent pregnancy after a cesarean delivery. Eastman (1950) described a 30-percent postcesarean vaginal delivery rate at Johns Hopkins Hospital. He also reported a 2-percent uterine rupture rate and associated 10-percent maternal mortality rate. As modern techniques made cesarean delivery safer, observational studies during the 1960s suggested that postcesarean vaginal delivery was a reasonable option (Pauerstein, 1966, 1969). Germane to this is that through the 1960s, the overall cesarean delivery rate approximated only 5 percent. Since then, as the primary cesarean rate has escalated, the repeat cesarean delivery rate followed (Rosenstein, 2013).
During the 1980s, a National Institutes of Health (NIH) Consensus Development Conference on Vaginal Birth After Cesarean (1981) was convened, and the participants questioned the necessity of routine repeat cesarean delivery. With support and encouragement from the American College of Obstetricians and Gynecologists (1988, 1994), enthusiastic attempts were begun to increase the practice rate of vaginal birth after cesarean—VBAC. These attempts were highly successful, and VBAC rates rose from 3.4 percent in 1980 to a peak of 28.3 percent in 1996. This rate and a concomitant decline in total cesarean delivery rate for the United States, are shown in Figure 31-1. Also, a new lexicon was developed to describe these practices and outcomes (Table 31-1).
Total, primary, and low-risk cesarean delivery (CD) rates and vaginal birth after previous cesarean (VBAC) rates in the United States, 1989–2018. Epochs denoted within rectangles represent contemporaneous ongoing events related to these rates. ACOG = American College of Obstetricians and Gynecologists; NIH = National Institutes of Health; PB = practice bulletin. (Data from Hamilton, 2015, 2016; Martin, 2019; National Institutes of Health: NIH Consensus Development Conference, 2010.)
TABLE 31-1Acronyms Used to Describe Management of Women with a Prior Cesarean Delivery ||Download (.pdf) TABLE 31-1Acronyms Used to Describe Management of Women with a Prior Cesarean Delivery
|CD: cesarean delivery|
TOL: trial of labor
VBAC: vaginal birth after CD
TOLAC: trial of labor after CDERCD: elective repeat cesarean delivery