A COMPARISON OF MISOPROSTOL AND PROSTAGLANDIN E(2) GEL FOR PREINDUCTION CERVICAL RIPENING AND LABOR INDUCTION

OBJECTIVE: Our purpose was to compare the safety and efficacy of intra vaginal misoprostol versus intracervical prostaglandin E(2) (dinoprost one) gel for preinduction cervical ripening and induction of labor. ST UDY DESIGN: One hundred thirty-five patients with indications for indu ction of labor and unfavorable cervices were randomly assigned to rece ive either intravaginal misoprostol or intracervical dinoprostone. Fif ty microgram tablets of misoprostol were placed in the posterior vagin al fornix every 3 hours for a maximum of six doses. Prostaglandin E(2) in gel form, 0.5 mg, was placed into the endocervix every 6 hours for a maximum of three doses. Medication was not given after either spont aneous rupture of membranes or beginning of active labor. RESULTS: Amo ng 135 patients enrolled, 68 received misoprostol and 67 received dino prostone. The average interval from start of induction to vaginal deli very was shorter in the misoprostol group (903.3 +/- 482.1 minutes) th an in the dinoprostone group (1410.9 +/- 869.1 minutes) (p < 0.001). O xytocin augmentation of labor occurred more often in the dinoprostone group (65.7%) than in the misoprostol group (33.8%) (P < 0.001). There were no significant differences between routes or delivery, Ten of th e misoprostol-treated patients (14.7%) and 13 of the dinoprostone-trea ted patients (19.4%) had cesarean deliveries. There was a higher preva lence of tachysystole (six or more uterine contractions in a 10-minute window for two consecutive 10-minute periods) in the misoprostol grou p (36.7%) than in the dinoprostone group (11.9%) (p < 0.001). However, there were no significant differences in frequency of uterine hyperst imulation or hypertonus. There was a higher prevalence of meconium pas sage in the misoprostol group (27.9%) than in the dinoprostone group ( 10.5%) (p < 0.05). There was no significant difference in frequency of abnormal fetal heart rate tracings, 1- or 5-minute Apgar scores < 7, neonatal resuscitations, or admissions to the neonatal intensive care unit between the two groups. CONCLUSIONS: Vaginally administered misop rostol is an effective agent for cervical ripening and induction of la bor; however when given at this dosage, it is associated with a higher prevalence of tachysystole and meconium passage than is dinoprostone. Further studies to compare the safety of misoprostol to that of dinop rostone and to delineate an optimal dosing regimen for misoprostol are needed.