Comparison of Misoprostol and Evening Primrose Oil on Cervical Preparation Before Gynecological Surgery

This study aimed to evaluate the efficacy and safety of evening primrose oil (EPO) for cervical ripening before gynecologic procedures and compare it to misoprostol. In this study, 40 hysteroscopy and dilation and curettage candidates were enrolled. Patients were randomly assigned to receive either 2000 mg of vaginal EPO (n = 20) or 200 μg of vaginal misoprostol (n = 20) 2 hours before the expected procedure. The measured outcomes were the size of the Hegar dilator that passed through the cervix effortlessly, uterine cervicovaginal complications, and drug-related side effects. The two groups were not significantly different in age, number of gravity, parity, type of delivery, and menopausal status (P > .05). The mean ± SD size of the first dilator was 5.25 ± 1.55 in the misoprostol group and 7.30 ± 1.08 in the EPO group (P < .001). The pain complaint in the EPO group was significantly lower (P = .027), but the two groups were not significantly different in terms of other complications. No cases of uterine or cervical rupture were seen in either group. The present study showed that 2000 mg of vaginal EPO was significantly more effective for cervical ripening than 200 μg of vaginal misoprostol before gynecological surgery. Therefore, it is recommended to use EPO as an alternative to misoprostol.