Cervical Ripening with Low-Dose Prostaglandins in Planned Vaginal Birth after Cesarean

OBJECTIVES To compare uterine rupture, maternal and perinatal morbidity rates in women with one single previous cesarean after spontaneous onset of labor or low-dose prostaglandin-induced cervical ripening for unfavourable cervix. STUDY DESIGN This was a retrospective cohort study of 4,137 women with one single previous cesarean over a 22-year period. Inpatient prostaglandin administration consisted in single daily local applications. RESULTS Vaginal delivery was planned for 3,544 (85.7%) patients, 2,704 (76.3%) of whom delivered vaginally (vaginal birth after Cesarean (VBAC) rate = 65.4%). Among women receiving prostaglandins (n=515), 323 (62.7%) delivered vaginally. Uterine rupture (0.7% compared with 0.8%, OR 1.1, 95% CI 0.4-3.4, p=0.88), maternal (0.9% compared with 1.2%, OR 1.3, 95% CI 0.5-3.2, p=0.63) and perinatal (0.3% compared with 0.8%, OR 2.4, 95% CI 0.7-8.5, p=0.18) morbidity rates did not differ significantly between patients with spontaneous onset of labor and those receiving prostaglandins, nor did these rates differ according to the planned mode of delivery. CONCLUSION In comparison with patients with spontaneous labor, inducing cervical ripening with low-dose prostaglandins in case of unfavourable cervix is not associated with appreciable increase in uterine rupture, maternal or perinatal morbidity.