Vaginal misoprostol for cervical priming before operative hysteroscopy: a randomized controlled trial.

OBJECTIVE: To investigate the effectiveness of vaginal misoprostol for cervical priming before operative hysteroscopy and to assess the cervicouterine complications related to cervical dilatation and hysteroscopic surgery in nulliparous women.

METHODS: One hundred fifty-two women with definite intrauterine lesions were randomly assigned to receive either 200 microg vaginal misoprostol or placebo. Cervical response and outcome and complications of operative hysteroscopy were assessed.

RESULTS: Thirty-five subjects were needed in each arm to detect a type I error of 0.01 with a power of 0.99. The mean cervical dilatation estimated by Hegar dilator was significantly different between the treated group (7.3 +/- 0.7 mm) and the control group (3.8 +/- 1.1 mm, P <.001). In the misoprostol group, 55 (75.3%) patients needed cervical dilation, compared with 75 (94.9%, P =.001) in the placebo group. The median time of cervical dilation to Hegar number 9 was significantly shorter in the treated group (40 seconds) compared with the control group (120 seconds, P <.001). The mean operative time was significantly shorter in the treated group (36.4 +/- 10.9 minutes) compared with the control group (45.9 +/- 14.2 minutes, P <.001). Cervical tears occurred in nine (11.4%) patients in the control group and in one (1.4%, P =.018) in the misoprostol group. Creation of a false tract was more common in the control group. Two uterine perforations occurred in the placebo group.

CONCLUSION: Vaginal misoprostol applied before operative hysteroscopy reduced the need for cervical dilation, facilitated hysteroscopic surgery, and minimized cervical complications.