Effect of a short-term vitamin E supplementation on oxidative stress in infertile PCOS women under ovulation induction: a retrospective cohort study

BACKGROUND: Vitamin E, which is critically important in the whole process of reproduction, can antagonize the oxidative stress caused by the oxygen free radicals and antioxidant imbalance and regulate normal physiological function of the reproductive system. The effect of short-term supplementation of vitamin E on outcomes of infertile women with polycystic ovary syndrome (PCOS) when they underwent ovulation induction with clomiphene citrate (CC) and human menopausal gonadotropin (HMG) remains unknown. METHODS: This was a retrospective cohort clinical trial from October 2015 to April 2017. A total of 321 PCOS cases underwent ovulation induction with CC and HMG. Patients in group A (n = 110) did not receive vitamin E while patients in group B (n = 105) and group C (n = 106) received oral treatment of vitamin E at 100 mg/day during follicular phase and luteal phase, respectively. RESULTS: It was observed no significant differences of ovulation rate, clinical pregnancy rate, and ongoing pregnancy rate among the three groups. It was interesting that dosage of HMG were significant lower in group B compared with those in group A and group C (P<0.05). CONCLUSIONS: A short-term supplementation of vitamin E can improve oxidative stress, and reduce exogenous HMG dosage to lower the economic cost with a similar pregnancy rate in the ovulation induction cycle. However, the supplementation does not alter the pregnancy rate in the ovulation induction cycle. TRIAL REGISTRATION: ChiCTR-OOC-14005389, 2014.