Cervical preparation using laminaria with adjunctive buccal misoprostol before second-trimester dilation and evacuation procedures: a randomized clinical trial

Edelman AB

Buckmaster JG

Goetsch MF

Nichols MD

Jensen JT

American Journal of Obstetrics & Gynecology
Feb 2006


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


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.


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).


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.