A RANDOMIZED TRIAL OF EXTRAAMNIOTIC SALINE INFUSION VERSUS LAMINARIA FOR CERVICAL RIPENING

Objective: To compare extra-amniotic saline infusion versus laminaria for cervical ripening and labor induction. Methods: Patients of at lea st 34 weeks' gestation with a Bishop score of 3 or less were randomize d to either laminaria ripening for 6 hours or more followed by oxytoci n induction versus initiation of extra-amniotic saline infusion at the start of oxytocin induction. Indications for induction included 41 we eks' gestation or greater, hypertensive disease, diabetes, oligohydram nios, suspect fetal growth, and nonreassuring fetal testing. Results: There were no significant differences in maternal age, race, parity, g estational age, or indications for induction between the two groups (e xtra-amniotic saline infusion group, n = 26, laminaria group, n = 26). After only 3 hours of oxytocin induction, patients in the extra-amnio tic saline infusion group achieved an identical distribution of Bishop scores compared with the patients in the laminaria group after 6 hour s or more of pre-induction ripening as well as 3 hours of oxytocin ind uction. There were no differences in rates of cesarean delivery (extra -amniotic saline infusion 35%, laminaria 35%), infectious complication s, or neonatal outcomes between the two groups. The induction-to-deliv ery interval (+/- standard deviation) was significantly shortened with extra-amniotic saline infusion (extraamniotic saline infusion 12.9 +/ - 5.7 hours versus laminaria 16.9 +/- 7.1 hours, P = .03). In addition , fewer cesarean deliveries were performed for failed inductions (cerv ix less than 5 cm dilated) in the extra-amniotic saline infusion group (one of 26 versus six of 26, P = .049). Conclusion: Extra-amniotic sa line infusion offers potential advantages over the use of laminaria. E xtra-amniotic saline infusion saves a significant amount of time both by obviating the need for pre-induction cervical ripening and in short ening the induction-to-delivery interval. Also, fewer patients require d cesarean delivery for failed induction of labor with extra-amniotic saline infusion.