Polycystic Ovary Syndrome and Ovulation Induction

Abstract

Polycystic ovary syndrome (PCOS) is likely the most common cause of anovulatory infertility. Although many options are available for ovulation induction in these patients, there is currently no evidence-based algorithm to guide the initial and subsequent choices of ovulation induction methods. In obese women with PCOS, mild to moderate weight loss results in improvement of ovulatory dysfunction, and should be advocated at the onset of the evaluation. Clomiphene citrate is currently the 1st line medical therapy for ovulation induction. Glucocorticoids do not result in consistent ovulation and have significant side effects. Exogenous pulsatile GnRH treatment has low ovulation and pregnancy rates with a high risk of miscarriage. The most commonly used medical agents for ovulation induction in clomiphene-resistant women with PCOS are parenteral gonadotropins. Various gonadotropin preparations and different protocols are available; however the risk of multiple pregnancy and ovarian hyperstimulation is high with gonadotropin therapy. The frequent association between PCOS and insulin resistance has prompted recent studies on the effect of insulin-sensitizing agents on spontaneous and as an adjuvant to conventional ovulation induction therapies. Overall, the improvement in ovulation with insulin sensitizing drugs is modest, and unresolved issues such as variability in ovarian response remain to be addressed in future studies. Nevertheless, these agents may be beneficial in a subset of PCOS patients. Surgical ovulation induction methods such as ovarian diathermy have been reported to be moderately effective. However, due to the inherent associated risks and unknown effect on long-term reproductive potential, this modality should be reserved for patients who are clomiphene-resistant and unable or unwilling to proceed to gonadotropin therapy.