RESUMO
It is estimated that 5-10% of women of reproductive age have polycystic ovarian syndrome (PCOS). While insulin resistance is not part of the diagnostic criteria for PCOS, its importance in the pathogenesis of PCOS cannot be denied. PCOS is associated with insulin resistance independent of total or fat-free body mass. Post-receptor defects in the action of insulin have been described in PCOS which are similar to those found in obesity and type 2 diabetes. Treatment with insulin sensitizers, metformin and thiazolidinediones, improve both metabolic and hormonal patterns and also improve ovulation in PCOS. Recent studies have shown that PCOS women have higher circulating levels of inflammatory mediators like C-reactive protein, tumour necrosis factor-alpha, tissue plasminogen activator and plasminogen activator inhibitor-1 (PAI-1). It is possible that the beneficial effect of insulin sensitizers in PCOS may be partly due to a decrease in inflammation.