Apart from the risk of uterine rupture at vaginal delivery after a previous cesarean birth, placental complications, including abruption and placenta previa, reportedly are more common in these women. This large-scale retrospective cohort study sought to determine whether cesarean delivery of a first infant correlates with a higher risk of antepartum stillbirth in the second pregnancy. The study population included all second births in Scotland in the years 1992–1998. In surveying 120,633 singleton second births, there were 68 antepartum stillbirths among 17,754 women who previously had a cesarean delivery. The incidence was 2.39 per 10,000 women per week. In 102,879 women who previously delivered vaginally, the corresponding figure was 1.44. The excessive risk of unexplained stillbirth in women with a previous cesarean delivery was apparent from 34 weeks gestational age (hazard ratio, 2.23; 95% confidence interval [CI], 1.48–3.36). Controlling for maternal characteristics and the outcome of first pregnancies did not substantially alter the risk (hazard ratio, 2.74; 95% CI, 1.74–4.30). The absolute risk of unexplained stillbirth at or after 39 weeks gestation was 1.1 per 1000 women having a previous cesarean delivery and 0.5 per 1000 in those who had not. The chief determinant of the excess of stillbirths in women with a previous cesarean delivery was unexplained stillbirth. The increased risk was not limited to deliveries at or after 41 weeks gestation. The findings were unchanged when only women delivering at term in their first pregnancy were analyzed. For unexplained stillbirths at or after 34 weeks gestation, median birth weight in women having a previous cesarean delivery was less than in those whose first deliveries were vaginal. These associations were confirmed on multivariate analysis. Women having cesarean delivery are more likely than those delivering vaginally to have an antepartum stillbirth in their second pregnancy. The major reason is an excess of unexplained stillbirths. Possibly ligating major uterine vessels affects uterine blood flow in later pregnancies. Another possible explanation is abnormal placentation secondary to the uterine scar.