Randomized trial of oral misoprostol before endometrial biopsy

To determine if the use of oral misoprostol in women undergoing endometrial biopsy reduces procedural discomfort.

Women undergoing endometrial biopsy were randomized to receive either 400 microg misoprostol or a vitamin B6 placebo orally 12 hours prior to the procedure, and were stratified based on menopausal status. The primary outcome was procedural discomfort on a visual analogue scale (0-10). Secondary outcomes included the need to dilate the cervix or use a tenaculum, and side effects. Subgroup analyses were planned for premenopausal and postmenopausal women separately. Sample size calculation was based on detecting a 50% reduction in pain, with alpha = 0.05 and beta = 0.10, in the premenopausal group.

A total of 72 women (49 premenopausal and 23 postmenopausal) were enrolled; 35 received misoprostol (23 premenopausal and 12 postmenopausal) and 37 received placebo (26 premenopausal and 11 postmenopausal). There were no significant differences in procedural discomfort (misoprostol vs. placebo 5.8 +/- 2.9 vs. 5.5 +/- 3.2, P = 0.77; premenopausal women 4.9 +/- 3.3 vs. 5.1 +/- 3.1, P = 0.85; postmenopausal women 7.1 +/- 1.9 vs. 7.1 +/- 2.3, P = 0.99), need to dilate the cervix (6.1% vs. 5.6%, P = 0.93) or use a tenaculum (44.1% vs. 48.6%, P = 0.70). Significantly more women in the misoprostol group experienced nausea (31.4% vs. 2.7%, P = 0.001), diarrhea (20.0% vs. 2.7%, P = 0.02), abdominal pain (22.9% vs. 5.4%, P = 0.03), menstrual-like cramping (42.9% vs. 2.7%, P < 0.001) and vaginal bleeding (11.4% vs. 0%, P = 0.03).

The use of 400 microg oral misoprostol 12 hours prior to endometrial biopsy did not reduce procedural discomfort and was associated with more side effects than use of placebo. This finding was noted in all women as well as among subgroups of premenopausal and postmenopausal women.