Comparison of the effect of Evening primrose oil with Misoprostol on cervical ripening before hysteroscopy in women without a previous vaginal delivery. a single-blind clinical trial

Abstract

Hysteroscopy, a minimally invasive method for evaluating the uterine cavity, has become an essential diagnostic and treatment method. One of the major problems of hysteroscopy surgery is the difficulty in placing the hysteroscopy (especially the resectoscope) in the cervical canal, which is associated with complications such as cervical rupture, creation of a false passage, uterine perforation, and bleeding. These complications may be reduced by adequate preparation of the cervix (cervical preparation) before hysteroscopy. In this context, E-series prostaglandins such as misoprostol effectively dilate and soften the cervix. However, studies have reported that misoprostol has side effects that have limited its use. Therefore, it is important to find alternatives with fewer side effects in adequate cervical preparation for hysteroscopy, in which the use of herbal medicine is emphasized. In this study, we compared the effect of evening primrose oil (EPO) with misoprostol for cervical ripening before hysteroscopy in women without a history of vaginal delivery. Methods: In this randomized clinical trial, 100 women candidates for hysteroscopy who visited Al-Zahra Hospital in Tabriz during 2020 were included in the study. These patients were divided into two groups (50 patients in each group). The first group received 1000 mg vaginal evening primrose oil capsules 6 hours before hysteroscopy, and the second group received 200 micrograms vaginal misoprostol tablets. After surgery, patients in both groups were evaluated for the average size of the first bogie inserted into the cervix with pressure, as well as cervical and vaginal complications and drug side effects. Results: The average size of the first bogie in the misoprostol group was larger than that in the evening primrose oil group (p=0.025). During the hysteroscopy procedure, no uterine, cervical, or vaginal complications were observed. However, drug side effects such as vaginal bleeding, fever, shivering, nausea, and diarrhea were all more common in patients who received misoprostol than in patients who received evening primrose oil.