In the proposed study, 40 adolescents and young adults with PCOS and 40 age-comparable control subjects will be evaluated for metabolic disturbances and elevated liver fat using noninvasive and state-of-the-art techniques including MRI, dual-energy x-ray absorptiometry and an oral glucose tolerance test in order to fully assess the metabolic and body composition differences between these groups. This research proposal represents a critical step in understanding the metabolic and cardiovascular comorbidities of PCOS and their relationship to NAFLD. The investigator hopes to use the results generated by this research proposal in order to lay the groundwork for the prevention and treatment of metabolic disorders in adolescents with PCOS. The overarching goal is to decrease and prevent lifelong morbidity associated with this common disorder.