Cervical ripening using vaginal misoprostol before hysteroscopy: a double-blind randomized trial.

STUDY OBJECTIVE: The aim of this study was to evaluate the use of vaginal misoprostol to decrease both the force required to dilate the cervix and the pain experienced during a hysteroscopy.

DESIGN: Randomized clinical trial (RCT) (Canadian Task Force classification I).

SETTING: University hospital gynecology clinic.

PATIENTS: A total of 101 patients needing a diagnostic hysteroscopy. Fifty patients were randomized to the misoprostol group and 51 to the placebo group. Patient characteristics were similar in the 2 groups.

INTERVENTIONS: Self-administration of 400 microg of vaginal misoprostol or vaginal placebo 12 to 24 hours before a hysteroscopy.

MEASUREMENTS AND MAIN RESULTS: The force needed to dilate the cervix was assessed by a tonometer, and pain was measured by a visual analog scale. The force to dilate the cervix to 6mm was significantly less in the misoprostol group (5.0 vs 7.5N, p=.02). Pain-related measurements after dilatation of the cervix to 6mm were significantly reduced in the misoprostol group (42.1 vs 57.2, p=.004). The main side effect reported with the use of the drug was pelvic cramping.

CONCLUSION: The use of 400 microg of vaginal misoprostol 12 to 24 hours before hysteroscopy reduces the pain and the force needed to dilate the cervix, with only mild side effects.