Adipose Tissue and Polycystic Ovary Syndrome (PCOS)(EIFFEL)

Inclusion Criteria: * Female * Age \> 20 and \< 40 * Weight stable (change of less than 3 kg in the last 8 weeks) * BMI \< 40 kg/m2 or \> 27 kg/m2 Supplemental inclusion criteria for PCOS women: * NIH criteria - confirmed by subjects' medical records. Exclusion Criteria: * Male * Women who are pregnant or lactating (breast feeding) * Post-menopausal women * Women with hysterectomy * Diagnosed with diabetes, or have a fasting blood sugar \> 126 mg/dL. * Untreated or symptomatic thyroid disease. * Impaired kidney or liver function, as evidenced by your blood work * Hypertension/ high blood pressure or are taking blood pressure medications * Use of oral contraceptives or hormone replacement therapy. * History of drug or alcohol abuse (\> 3 drinks per day) in the last 5 years, or psychiatric disease prohibiting adherence to study protocol. * History of cancer within the last 5 years. * History of organ transplant. * History of HIV, active Hepatitis B or C, or Tuberculosis. * History of heart attack/ myocardial infarction. * Presence of clinically significant abnormalities on EKG. * Current smokers (smoking within the past 3 months) * Use of any medications known to influence glucose, fat and/or energy metabolism within the last 3 months (e.g., growth hormone therapy, glucocorticoids \[steroids\], etc.). Metformin for women with PCOS is allowed.