Objective: To evaluate the induction-to-abortion time of 3 pharmacokinetic-based protocols at 13-20 weeks of gestation.
Study design: A randomized trial was conducted on 153 patients. The oral group (n = 51) received 100 microg misoprostol orally every 2 hours, the vaginal group (n = 51) received 200 microg misoprostol vaginally every 4 hours, and the sublingual group (n = 51) received 100 microg misoprostol sublingually every 2 hours.
Results: The mean induction-to-delivery time was shorter in the sublingual group (mean, 651 +/- 507) as compared to the vaginal group (mean, 1,056 +/- 634, p = 0.01). The number of patients who delivered within 12 hours was significantly higher in the sublingual group (n = 39, 78%) as compared to the oral (n = 26, 52%) and vaginal (n = 20, 40%) groups (p < 0.001). The numbers of patients who delivered within 24 hours were comparable in the sublingual (n = 47, 94%) and oral (n = 46, 92%) groups but higher than in the vaginal group (n = 39, 78%; p = 0.02). The total misoprostol dose was 543 +/- 422 microg in the sublingual group, 878 +/- 533 microg in the vaginal group and 741 +/- 413 microg in the oral group (p < 0.001).
Conclusion: A pharmacokinetic-based application of 100 microg of sublingual misoprostol every 4 hours is more effective for induction of second-trimester abortion as compared to 100 microg oral misoprostol every 2 hours and 200 microg vaginal misoprostol every 4 hours.