Oral misoprostol prior to operative hysteroscopy does not enhance cervical dilation or improve operative time: A prospective randomized, double blind, placebo-controlled trial

Abstract

Objective: Misoprostol is a synthetic prostaglandin E1 analog demonstrated to induce cervical ripening for induction of labor. Some prior studies have demonstrated enhanced cervical dilation and decreased operative times with the vaginal administration of misoprostol but a study using oral dosing failed to demonstrate effectiveness in postmenopausal women. The objective of this study was to determine if oral misoprostol prior to operative hysteroscopy would enhance cervical dilation and decrease operative time.Design: Prospective randomized double blind placebo-controlled trial.Materials/Methods: All patients scheduled for planned operative hysteroscopy at our University based Obstetrics and Gynecology residency training program were included for study. Patients were randomized to receive an opaque coded envelope that contained capsules of either misoprostol (400 micrograms) or placebo. Group selection was determined by random permuted blocks. Patients were instructed to ingest the capsules 12 hours prior to the planned procedure. Data collected included time required for cervical dilation and hysteroscopy, first dilator used that encountered resistance, subjective ease of the procedure, patient pain, side-effects, and the incidence of complications. Data analysis was performed using the Mann-Whitney U test for continuous variables and Chi-square test for categorical variables.Results: Forty-six patients were enrolled in the study and randomized to two groups (active medication and placebo)containing 23 subjects each. The groups were similar in age, number of prior vaginal deliveries, and menopausal status. The groups did not differ for time of dilation (p = 0.830), time of hysteroscopy (p = 0.243), dilator with first resistance (p = 0.402), ease of the procedure (p = 0.302) or pain rating after surgery (p = 0.880). Discomfort and side effects were similar in both groups. One cervical laceration and one false track were found in the misoprostol group. There were no uterine perforations.Conclusions: Although possibly limited by sample size, this pilot study failed to demonstrate any clinical benefit for oral administration of misoprostol with regard to time needed for dilation, time needed for hysteroscopy, dilator with first resistance, ease of procedure, and post-operative pain. Further investigation with a larger sample size is needed for verification of these findings.Supported by: None. Objective: Misoprostol is a synthetic prostaglandin E1 analog demonstrated to induce cervical ripening for induction of labor. Some prior studies have demonstrated enhanced cervical dilation and decreased operative times with the vaginal administration of misoprostol but a study using oral dosing failed to demonstrate effectiveness in postmenopausal women. The objective of this study was to determine if oral misoprostol prior to operative hysteroscopy would enhance cervical dilation and decrease operative time. Design: Prospective randomized double blind placebo-controlled trial. Materials/Methods: All patients scheduled for planned operative hysteroscopy at our University based Obstetrics and Gynecology residency training program were included for study. Patients were randomized to receive an opaque coded envelope that contained capsules of either misoprostol (400 micrograms) or placebo. Group selection was determined by random permuted blocks. Patients were instructed to ingest the capsules 12 hours prior to the planned procedure. Data collected included time required for cervical dilation and hysteroscopy, first dilator used that encountered resistance, subjective ease of the procedure, patient pain, side-effects, and the incidence of complications. Data analysis was performed using the Mann-Whitney U test for continuous variables and Chi-square test for categorical variables. Results: Forty-six patients were enrolled in the study and randomized to two groups (active medication and placebo)containing 23 subjects each. The groups were similar in age, number of prior vaginal deliveries, and menopausal status. The groups did not differ for time of dilation (p = 0.830), time of hysteroscopy (p = 0.243), dilator with first resistance (p = 0.402), ease of the procedure (p = 0.302) or pain rating after surgery (p = 0.880). Discomfort and side effects were similar in both groups. One cervical laceration and one false track were found in the misoprostol group. There were no uterine perforations. Conclusions: Although possibly limited by sample size, this pilot study failed to demonstrate any clinical benefit for oral administration of misoprostol with regard to time needed for dilation, time needed for hysteroscopy, dilator with first resistance, ease of procedure, and post-operative pain. Further investigation with a larger sample size is needed for verification of these findings. Supported by: None.