The effect of evening primrose oil on adolescent girl patients with PCOS: A double-blind placebo-controlled randomized study.

Objective: Polycystic ovary syndrome (PCOS) is a common disorder among women of reproductive age. The goal of the current study was to evaluate the effect of evening primrose oil (EPO) (Oenothera biennis) in adolescent girls with PCOS.

Materials and methods: In the current double-blind and randomized controlled research, 76 patients completed the study in two groups (38 in the placebo and 38 in the EPO groups). The patients were asked to take oral placebo or EPO (1000 mg/day) for 12 weeks. Biochemical, clinical, and ultrasonography assessments were performed. The data was analyzed using SPSS statistical software.

Results: After the intervention, the regulation of the menstrual cycle in the EPO group was different from that of the placebo group (p=0.04). The levels of insulin, testosterone, and free androgen index (FAI) in the EPO group were lower than those of the placebo group (p<0.05). The sex hormone binding globulin (SHBG) levels in the EPO group were higher than those of the placebo group (p=0.01). While the number of immature follicles decreased in the EPO group, this difference was not statistically significant (p=0.8).

Conclusion: Overall, EPO administration for 12 weeks in young women with PCOS regulated the irregular menstrual cycle. In addition, the levels of insulin, testosterone, FAI, and SHBG changed. Therefore, EPO may be effective in improving hormonal and menstrual irregularities.