A randomized controlled trial of vaginal misoprostol for cervical priming before hysteroscopy

Objective: To evaluate the effectiveness and side effects of vaginal misoprostol for cervical dilation in nonpregnant women before hysteroscopy. Methods: Ninety-one women scheduled to have hysteroscopy were randomized to receive either vaginal misoprostol or placebo. Cervical response, outcome of hysteroscopy, and side effects of vaginal misoprostol were assessed. Results: The mean cervical dilatation estimated by Hegar dilator and the mean duration of hysteroscopy were significantly different between the treated group (7.0 +/- 1.0 mm [range 6-8.5] and 90.0 +/- 38.4 seconds [range 60-240], respectively) and the control group (3.8 +/- 1.2 mm [range 2-5.5] and 142.0 +/- 38.7 seconds [range 60-270]). In the misoprostol group, only three women (6.5%) needed cervical dilation before hysteroscopy, compared with 14 (31.1%) in the placebo group (P = .006). Cervical tears during hysteroscopy occurred in two patients (4.4%) in the control group and none in the misoprostol group. The two most common side effects of vaginal misoprostol were mild lower abdominal pain in 15 women (32.6%) and slight vaginal bleeding in 12 (26.1%). Both side effects were significantly different when compared with placebo (P < .001). Conclusion: Vaginal misoprostol lessens the cervical resistance in women undergoing hysteroscopy and facilitates the procedure, with only mild side effects. (C) 1999 by The American College of Obstetricians and Gynecologists.