OBJECTIVE: To determine which method of cervical ripening results in the lowest cesarean (CS) late in women with an unfavorable ceivix. STUDY DESIGN: Women undergoing an indicated induction of labor (IOI.) were randomized to Laminaria (IAMS) + oxytocin, EASI + oxytocin. or Prepidil™ (PREP), 0.5mg qfih (maxiimun two doses) + oxytocin PRN. Eligible women had a singleton gestation with intact membranes and were <2cm dilated (DU.) and <75% effaced. All patients were managed by ihe residents and MFM faculty at a single institution. We calculated that a sample of 417 women would have 80% power to detect a 50% reduction in the intergroup ('S rates (u = .05). RESULTS: For this interim analysis we studied the first 26-4 women: LAMS-91, EASI-81. PREP-92. The groups were similar with regard to parity, age. gestational age (39.5±2.3 wks), initial OIL, and indication for induction. The groups were also similar with regard to intrapartum epidural use, chorioamnionitis and birthweight. Postpartum there were no significant differences in the endometritis rales, high-risk nursery admissions or neonatal sepsis rates. EASI LAMS PREP p-value DIL & 12 hrs (cm) 4.3±3 3.4±2 2.2±2 .001 CS rate (%) 27 38 29 .2 Insertion-Delivery (hrs) 16±10 20±10 25±12 .0001 Delivered by 24 hrs (1) 8S 71 61 .001 CONCLUSIONS: EASI was associated with the shortest insertion to delivery internal. From this interim analysis we concluded that PREP offered no advantage, and we will complete the trial using IAMS and KASI in order to determine if a significant difference exists in the CS rates.