Cervical Preparation Using Laminaria with Adjunctive Buccal Misoprostol Before Second-trimester Dilation and Evacuation Procedures: a Randomized Clinical Trial

Objective: This study was undertaken to determine whether buccal misoprostol improves cervical preparation achieved with laminaria before second-trimester dilation and evacuation procedures.

Study Design: A randomized, double blind, placebo-controlled trial of preoperative cervical preparation with overnight laminaria and either buccal placebo or 400 microg buccal misoprostol approximately 90 minutes before second-trimester surgical abortion. Block randomization was used to provide balanced enrollment into 2 separate gestational age study groups: early (13-15(6/7)) and mid (16-20(6/7)) second trimester. Surgeons tested maximal cervical dilation by inserting the largest dilator that could be passed through the cervical os without force. Subject demographics and preprocedure symptoms were tracked.

Results: Groups were similar in regard to age, gravity, parity, delivery type, and gestational age. Data were analyzed from 125 women in the 13 to 15(6/7) (30 misoprostol, 32 placebo) and 16 to 20(6/7) (31 misoprostol, 32 placebo) gestational age groups. Overall, misoprostol treatment did not improve the initial mean dilation achieved with laminaria alone in either the 13 to 15(6/7) (46.0 fr +/- 5.0; placebo 45.0 fr +/- 6.2, P = .68) or 16 to 20(6/7) (50.9 fr +/- 5.6, placebo 48.9 fr +/- 5.2, P = .16) groups. However, a subanalysis of gestations 19 weeks or more demonstrated significantly greater dilation in the misoprostol group (53.6 fr fr +/- 5.3, placebo 48.5 fr +/- 5.0, P = .01). Subjects receiving misoprostol reported significantly more cramping than those receiving placebo (13-15(6/7) weeks misoprostol 25/30, 83%; placebo 17/32, 53%, P = .02; 16-20(6/7) week misoprostol 25/31, 81%, placebo 16/32, 50%, P = .02).

Conclusion: Cervical dilation with laminaria is augmented by 400 microg buccal misoprostol in gestations 19 weeks or more, but not in earlier gestations. Misoprostol causes more abdominal cramping.