RANDOMIZED TRIAL OF MISOPROSTOL AND EXTRAAMNIOTIC SALINE INFUSION FORCERVICAL RIPENING AND LABOR INDUCTION

Objective: To compare the cesarean rates in women undergoing induction of labor with unfavorable cervices who receive either misoprostol or extra-amniotic saline infusion. Methods: We assigned 250 women undergo ing indicated induction of labor randomly to misoprostol (50 mu g ever y 4 hours for three doses with or without oxytocin) or extraamniotic s aline infusion and oxytocin. Each eligible subject had a singleton ges tation, vertex presentation, intact membranes, cervical dilation no mo re than 2 cm, and effacement no more than 50%. Results: Two hundred fo rty-eight women were studied after two exclusions; 120 were assigned t o misoprostol, and 128 to extra-amniotic saline infusion. This sample size ensured an 80% chance of detecting an intergroup difference in ce sarean rates of at least two-fold. The groups were similar in age, rac e, parity, indication for induction, and gestational age. The extra-am niotic saline infusion group had a significantly lower median initial dilation; however, at 12 hours, this group was significantly more dila ted. The groups also were similar in epidural use, chorioamnionitis ra tes, endometritis rates, birth weights, and neonatal outcomes. Overall , 23% of women underwent cesarean deliveries, 18% and 27% for the miso prostol and extra-amniotic saline infusion groups, respectively (P = . 12). There were no significant differences in the median time to eithe r vaginal or cesarean delivery between the two groups. Eighty-one perc ent of women were delivered in less than 24 hours from initiation of i nduction; 78% in the misoprostol group, and 84% in the extra-amniotic saline infusion group (P = .19). Conclusion: Both methods of labor ind uction appear to be equally effective in this group of women at high r isk for cesarean delivery and prolonged induction of labor. (C) 1998 b y The American College of Obstetricians and Gynecologists.