Polycystic ovary syndrome and insulin: our understanding in the past, present and future.

Insulin resistance is prevalent in women with polycystic ovary syndrome (PCOS), and plays a critical pathophysiologic role in both the metabolic and reproductive complications of PCOS. This review focuses on the contribution of insulin resistance to anovulation in PCOS and to the high risk for Type 2 diabetes, metabolic syndrome and early cardiovasular disease. Key points for clinicians emphasized by this review are the following: PCOS is a clinical diagnosis and alternative diagnoses must be excluded; PCOS carries an inherent risk of insulin resistance and, hence, metabolic consequences for which women with PCOS should be screened regardless of BMI or degree of obesity; and PCOS is associated with infertility and this should be discussed early on in care of women diagnosed with PCOS, recognizing that there are several possible strategies to address infertility in women with PCOS, each with its own risks and benefits.