A comparison of two methods of labor induction with vaginal misoprostol

Abstract Objectives: To evaluate if labor induction with 50 μg of vaginal misoprostol twice per day is as effective as and safer than 100 μg used once per day. Methods: Misoprostol was used to induce labor in 204 consecutive pregnant women assessed as needing labor induction, 104 at the University Hospital of the West Indies in Kingston, Jamaica, and 100 at the Victoria Jubilee Hospital, also in Kingston. At the former institution the women were administered 100 μg of misoprostol once per 24 h and at the latter 50 μg every 12 h. The doses were repeated if there was no cervical change or if the woman was not in labor. Bishop scores were determined before initiation of induction and again 12 h later. Women's records were reviewed after 24 h to determine delivery outcome. Results: The indications for labor induction were similar in each group. There was no significant difference in the group demographics. In the group given 50 μg of misoprostol twice per day the mean time±S.D. from insertion of misoprostol to delivery was significantly shorter than in the other group (560.14±269.20 min vs. 729.90±471.65 min; P P P =0.04) and admission to the special care nursery (7% vs. 17%; P =0.03) in the group that had received 50 μg of misoprostol twice per day. Conclusions: A dose of 50 μg of misoprostol twice per day appears to be more efficient and safer than a dose of 100 μg once per day, but this may partially be due to weaknesses in the study design.