CHAPTER 31: Prior Cesarean Delivery

The occurrence of pregnancy after a Caesarean section, however, is not always devoid of danger, cases have been reported in which the uterine cicatrix ruptured in the latter part of a subsequent gestation. It is also stated that the adhesions that sometimes form between the uterus and the abdominal wall occasionally exert a deleterious influence in subsequent pregnancies.

—J. Whitridge Williams (1903)

INTRODUCTION

From the above, there was an early appreciation for some of the major problems encountered in women with a prior cesarean delivery. Few issues in modern obstetrics have been as controversial as the management of these women. Indeed, the dangers associated with uterine rupture led to the oft-quoted remark by Cragin in 1916: “Once a cesarean, always a cesarean.” As we reach the 100-year mark of Cragin’s pronouncement, the issue remains largely unsettled.

100 YEARS OF CONTROVERSY

By the beginning of the 20th century, cesarean delivery had become relatively safe. But, as women survived the first operation and conceived again, they were now at risk for rupture of the uterine scar. Still, the specter of rupture did not did not result in strict adherence to repeat cesarean delivery. Indeed, Eastman (1950) described a 30-percent postcesarean vaginal delivery rate at Johns Hopkins Hospital. The uterine rupture incidence was 2 percent and associated with a 10-percent maternal mortality rate. During the 1960s, observational studies suggested that vaginal delivery was a reasonable option (Pauerstein, 1966, Pauerstein, 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 escalated, the rate for repeat cesarean delivery followed (Rosenstein, 2013).

During the 1980s, a National Institutes of Health (NIH) Consensus Development Conference (1981) was convened, and it 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 use of vaginal birth after cesarean—VBAC. These attempts were highly successful, and VBAC rates increased from 3.4 percent in 1980 to a peak of 28.3 percent in 1996. These rates, along with a concomitant decline in total cesarean delivery rates for the United States, are shown in Figure 31-1.

FIGURE 31-1

Total, primary, and low-risk cesarean delivery (CS) rates and vaginal birth after previous cesarean (VBAC) rates in the United States, 1989–2015. 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; National Institutes of Health: NIH Consensus Development Conference, 2010.)