Prospective randomized clinical trial of inpatient cervical ripening with stepwise oral misoprostol versus vaginal misoprostol

Abstract

ObjectiveTo compare the efficacy and safety of stepwise oral misoprostol versus vaginal misoprostol for cervical ripening prior to induction of labor.Study designTwo hundred and four women between 32 to 42 weeks of gestation with an unfavorable cervix (Bishop score ≤ 6) and an indication for labor induction were randomized to receive oral or vaginal misoprostol every 4 hours up to 4 doses. The oral misoprostol group received 50 μg initially followed by 100 μg in each subsequent dose. The vaginal group received 25 μg in each dose. The primary outcome was the interval from first misoprostol dose to delivery. The sample size calculation (n = 194) was based on an alpha of .05 and a beta of .20 to detect a 4-hour difference. Patient satisfaction and side effects were assessed by surveys completed after delivery. Statistical analyses were performed using Student t test, χ2 test, Fisher exact test, and ANOVA where appropriate.ResultsNinety three ( 45.6%) women received oral misoprostol; 111 (54.4%) received vaginal misoprostol. There was no difference in the average interval from first dose to vaginal delivery between the oral (19.3 ± 6.7 hrs ) and vaginal (18.0 ± 8.3 hrs, P = NS) groups. There was a trend towards a lower incidence of hyperstimulation in the oral group 2.2% vs. vaginal group 5.4%, P = NS. Eighteen patients in the oral group (19.4%) and 36 (32.4%) in the vaginal group underwent cesarean section (P < .05). This difference remained significant after controlling for confounders of cesarean delivery. There was no difference in side effects (nausea, vomiting, diarrhea, shivering) between groups but more patients in the vaginal group were dissatisfied with the use of misoprostol (14% vs. 7.5%, P = NS).ConclusionStepwise oral misoprostol (50 μg followed by 100 μg) is as effective as vaginal misoprostol (25 μg) for cervical ripening with a low incidence of hyperstimulation, lower rate of cesarean section, no increase in side effects and a trend towards improved patient satisfaction. ObjectiveTo compare the efficacy and safety of stepwise oral misoprostol versus vaginal misoprostol for cervical ripening prior to induction of labor. To compare the efficacy and safety of stepwise oral misoprostol versus vaginal misoprostol for cervical ripening prior to induction of labor. Study designTwo hundred and four women between 32 to 42 weeks of gestation with an unfavorable cervix (Bishop score ≤ 6) and an indication for labor induction were randomized to receive oral or vaginal misoprostol every 4 hours up to 4 doses. The oral misoprostol group received 50 μg initially followed by 100 μg in each subsequent dose. The vaginal group received 25 μg in each dose. The primary outcome was the interval from first misoprostol dose to delivery. The sample size calculation (n = 194) was based on an alpha of .05 and a beta of .20 to detect a 4-hour difference. Patient satisfaction and side effects were assessed by surveys completed after delivery. Statistical analyses were performed using Student t test, χ2 test, Fisher exact test, and ANOVA where appropriate. Two hundred and four women between 32 to 42 weeks of gestation with an unfavorable cervix (Bishop score ≤ 6) and an indication for labor induction were randomized to receive oral or vaginal misoprostol every 4 hours up to 4 doses. The oral misoprostol group received 50 μg initially followed by 100 μg in each subsequent dose. The vaginal group received 25 μg in each dose. The primary outcome was the interval from first misoprostol dose to delivery. The sample size calculation (n = 194) was based on an alpha of .05 and a beta of .20 to detect a 4-hour difference. Patient satisfaction and side effects were assessed by surveys completed after delivery. Statistical analyses were performed using Student t test, χ2 test, Fisher exact test, and ANOVA where appropriate. ResultsNinety three ( 45.6%) women received oral misoprostol; 111 (54.4%) received vaginal misoprostol. There was no difference in the average interval from first dose to vaginal delivery between the oral (19.3 ± 6.7 hrs ) and vaginal (18.0 ± 8.3 hrs, P = NS) groups. There was a trend towards a lower incidence of hyperstimulation in the oral group 2.2% vs. vaginal group 5.4%, P = NS. Eighteen patients in the oral group (19.4%) and 36 (32.4%) in the vaginal group underwent cesarean section (P < .05). This difference remained significant after controlling for confounders of cesarean delivery. There was no difference in side effects (nausea, vomiting, diarrhea, shivering) between groups but more patients in the vaginal group were dissatisfied with the use of misoprostol (14% vs. 7.5%, P = NS). Ninety three ( 45.6%) women received oral misoprostol; 111 (54.4%) received vaginal misoprostol. There was no difference in the average interval from first dose to vaginal delivery between the oral (19.3 ± 6.7 hrs ) and vaginal (18.0 ± 8.3 hrs, P = NS) groups. There was a trend towards a lower incidence of hyperstimulation in the oral group 2.2% vs. vaginal group 5.4%, P = NS. Eighteen patients in the oral group (19.4%) and 36 (32.4%) in the vaginal group underwent cesarean section (P < .05). This difference remained significant after controlling for confounders of cesarean delivery. There was no difference in side effects (nausea, vomiting, diarrhea, shivering) between groups but more patients in the vaginal group were dissatisfied with the use of misoprostol (14% vs. 7.5%, P = NS). ConclusionStepwise oral misoprostol (50 μg followed by 100 μg) is as effective as vaginal misoprostol (25 μg) for cervical ripening with a low incidence of hyperstimulation, lower rate of cesarean section, no increase in side effects and a trend towards improved patient satisfaction. Stepwise oral misoprostol (50 μg followed by 100 μg) is as effective as vaginal misoprostol (25 μg) for cervical ripening with a low incidence of hyperstimulation, lower rate of cesarean section, no increase in side effects and a trend towards improved patient satisfaction.