Randomized, double-blind trial of prostaglandin E2 intravaginal gel versus low-dose oxytocin for cervical ripening before induction of labor.

Objective: Our purpose was to compare two methods of preinduction cervical ripening in a randomized, double-blind clinical trial.

Study Design: Two intravaginal, 4 mg prostaglandin E2 gel applications administered 4 hours apart were compared with 10 hours of low-dose oxytocin (2 mU/min) in 200 patients undergoing preinduction cervical ripening.

Results: There were no differences in parity, initial Bishop scores, estimated gestational ages, indications for induction, or birth weights. Prostaglandin E2 gel was significantly better (p < 0.0001) at achieving a change in the Bishop score of 3 or more. The number of successful inductions was significantly greater (p < 0.0003) and the mean time to active labor was significantly shorter (p < 0.0002) in the prostaglandin E2 group than in the oxytocin group. More multiple-day inductions (p < 0.01) occurred in the oxytocin group, and fewer discharged patients who did not deliver infants (p < 0.03) were seen in the prostaglandin E2 gel group. There were no differences between patient groups in the cesarean section rate, meconium staining, hyperstimulation, and Apgar scores.

Conclusion: Two 4 mg doses of prostaglandin E2 intravaginal gel applied 4 hours apart are superior to low-dose oxytocin in producing cervical ripening and preparing for successful induction.