(1) Non-obese and obese women with PCOS between 18-40 years of age. (2) oligomenorrhea ( 8 menstrual periods annually), (3) biochemical hyperandrogenemia (elevated total or free testosterone), (4) normal thyroid function tests and serum prolactin, and (5) exclusion of 21 -hydroxylase deficiency by a fasting 17 -hydroxyprogesterone <200 ng/dl.41 (6) acceptable health on the basis of interview, medical history, physical examination, and laboratory tests (CBC, SMA20, urinalysis). (7) Signed, witnessed informed consent. (8) Ability to comply with study requirements.