Abstract

Background and Aim: Polycystic ovary syndrome (PCOS) is one of the most important reproductive and endocrine disorders in women. Evening primrose oil is a phytosterogenic plants, and there are many reports about the effects of phytoestrogens on the hypothalamus-pituitary axis. Regarding the side effects of existing drugs, the aim of this study was to evaluate the effect of evening primrose oil (EPO) on changes in sex hormones, serum glucose and insulin levels and insulin sensitivity in PCOS.

Methods: In this experimental study 30 female Sprague Dawley rats with regular sexual cycle were divided into five groups (n=6). Group 1: control. Group 2: (control treatment) received evening primrose oil gavage at dose of 1000mg/kg for 21 days. Group 3: PCOS induced by estradiol valerate. Group 4: After induction of PCOS received evening primrose oil gavage at dose of 1000mg/kg for 21 days. Group 5: After induction of PCOS received evening primrose oil gavage at dose of 2000mg/kg for 21 days. Finally, blood samples were collected from heart and then sex hormones, glucose and insulin concentrations were determined. The results were analyzed by SPSS software using one-way ANOVA and Duncan 's test.

Results: The FSH level increased significantly in the fourth and fifth groups compared to the third (p <0.05). Levels of LH and testosterone levels were significantly lower in the fourth and fifth groups than the third group (p <0.05). There was no significant difference in the level of FSH and LH among the other groups. The serum levels of insulin and glucose in the fourth and fifth groups were significantly lower than the third group (p <0.05). Also, insulin sensitivity was higher in the treatment groups than in the third group (p <0.05). There was no significant difference in insulin, glucose and insulin sensitivity among other groups.

Conclusions: By changing the concentration of FSH, LH and testosterone hormones in polycystic ovary syndrome, evening primrose oil, can reduce the complications of these hormonal changes. EPO also reduces insulin and serum glucose and increases insulin sensitivity in PCOS. With more complete studies, Evening primrose oil can be recommended as a good alternative to chemical drugs for the treatment of PCOS.