- The obesity epidemic in the United States is advancing at an accelerated pace. It is estimated that by 2015, 41% of U.S. adults will be obese as defined by a body mass index (BMI) of greater than 30 kg/m2. The U.S. government's 2010 Dietary Guidelines regard obesity as the single greatest health hazard in this century. Female adult obesity is associated with menstrual cycle irregularities, ovulatory dysfunction and a higher risk of obstetrical complications. This reproductive phenotype of obesity is worsened by further increases in BMI and is not solely due to anovulatory infertility. While the association of adiposity with subfertility is well documented in population studies, the underlying mechanisms remain poorly understood. The main objective of this proposal is to clarify the nature of the obesity-related reproductive endocrine abnormalities and identify potential etiologies amenable to therapy.