 Polycystic ovary syndrome PCOS affects 5-10 of women and may be viewed as the combination of hyperandrogenism with the classical features of the metabolic syndrome in young women. PCOS presents a unique opportunity to dissect the relationship between metabolic and cardiovascular risk and sleep disordered breathing SDB in a population where intrinsic effects of aging have not yet developed. Because a relationship between obstructive sleep apnea, insulin resistance and elevated testosterone levels has also been observed in men and in women without PCOS, insights gained from studies in PCOS will have broad implications. 