Objective: This study was undertaken to determine the risk of uterine rupture in patients induced with oxytocin or misoprostol after 1 or more previous cesarean sections.
Study design: Patients with 1 or more previous cesarean sections who delivered after 28 weeks' gestation between 1996 and 2002 were identified by database. Among 3533 total patients, rates of uterine rupture were compared among 4 groups: oxytocin induction (n = 430), misoprostol induction (n = 142), spontaneous labor (n = 2523), and repeat cesarean section without labor (n = 438). Statistical analysis included chi(2) test, Fisher exact test, unpaired t test, and Mantel-Haenszel test.
Results: Rate of rupture was increased in all inductions compared with that of the spontaneous labor group. Among patients with 1 prior cesarean, rupture rates with misoprostol and oxytocin induction were 0.8% and 1.1%, respectively.
Conclusion: Induction of labor with oxytocin or misoprostol is associated with a higher rate of uterine rupture compared with those who deliver after spontaneous labor. After 1 prior cesarean, rupture rate with misoprostol induction is not increased compared with oxytocin induction.