Preinduction cervical ripening. A randomized trial of intravaginal misoprostol alone vs. a combination of transcervical Foley balloon and intravaginal misoprostol.

OBJECTIVE: To determine if the addition of a mechanical ripening agent (transcervical Foley balloon) to a pharmacologic agent (intravaginal misoprostol) improves the efficiency of preinduction cervical ripening. STUDY DESIGN: Singleton patients with an indication for delivery, unfavorable cervix (Bishop score < or = 5) and no contraindication to labor were randomly assigned to two groups: misoprostol alone (25 micrograms intravaginally every 3 hours for no more than 12 hr) or combination therapy (25-French transcervical Foley balloon inflated to 50 mL of sterile water with identical intravaginal misoprostol dosing). All patients received a history and physical examination (including Bishop score), preripening ultrasound, electronic fetal heart rate and contraction monitoring (to rule out spontaneous labor and document fetal well-being). Multiple variables of perinatal outcome were analyzed, including the main outcome variables of ripening-to-delivery time and cesarean section rate. RESULTS: During August 1998 to August 1999, 81 patients were randomized, 40 to misoprostol alone and 41 to combination therapy. There were no differences between the groups with respect to maternal demographics, preripening Bishop score, maternal complications, intrapartum intervention or neonatal outcome. The misoprostol group spent longer periods of time in active labor, and there was a trend for the combination group to require oxytocin for longer intervals. These findings did not significantly affect the total ripening-to-delivery time or cesarean section rate which were similar for both groups. CONCLUSION: The addition of mechanical ripening with a transcervical Foley balloon to intravaginal misoprostol did not improve the efficiency of preinduction cervical ripening. Mechanical and pharmacologic cervical ripening agents appear to act independently rather than synergistically.

Preinduction cervical ripening techniques compared.

OBJECTIVE: To assess the clinical efficacy of pharmacologic, mechanical and combination techniques of cervical ripening. STUDY DESIGN: From March 1997 to August 1998, all cervical-ripening patients at Lehigh Valley Hospital were randomly assigned to three groups: intravaginal misoprostol, intracervical Foley catheter, or combination prostaglandin E2 (PGE2) gel and Foley catheter. Inclusion criteria included Bishop score < or = 5 and no contraindication to labor. The remaining delivery process was actively managed according to established guidelines. Multiple variables in perinatal outcome were analyzed, with the cesarean section rate and time from ripening to delivery as the main outcome variables. RESULTS: Of the 205 patients, 65 were randomized to the misoprostol group, 71 to the Foley group and 69 to the catheter-and-gel group. There were no differences between groups in delivery indications, maternal demographics, ultrasound findings, labor interventions, intrapartum times, mode of delivery, postpartum complications or neonatal outcomes. The misoprostol group demonstrated a higher rate of uterine tachysystole and required oxytocin less when compared to the two catheter groups. CONCLUSION: The higher rate of uterine tachysystole with misoprostol did not increase the cesarean section rate. The higher rate of oxytocin required by the two catheter groups did not increase the delivery time intervals. There appears to be no benefit to adding intracervical or intravaginal PGE2 gel to the intracervical Foley balloon. The misoprostol and catheter ripening techniques have similar safety and efficacy.