Sex Differences in Effects of Obesity on Reproductive Hormones and Glucose Metabolism in Puberty: The Health Influences of Puberty Study

Context: Obesity is known to impact reproductive function in adults, but little is known about its effects on reproductive hormones during puberty or sex differences in these effects. Objective: To assess sex differences in effects of obesity on reproductive hormones and their relationship to insulin sensitivity and secretion. Design: Cross-sectional study including anthropometrics, serum and urine reproductive hormone concentrations, and intravenous glucose tolerance testing (IVGTT) to assess acute insulin response to glucose (AIRg) and insulin sensitivity (Si). Setting: Outpatient academic clinical research center. Patients: Fifty-one normal weight (NW, BMI-Z=-0.11 +/- 0.77, age=11.5 +/- 1.7 years) and 53 obese (BMI-Z=2.22 +/- 0.33, age=10.9 +/- 1.5 years) girls (n=54) and boys (n=50), Tanner stage 2-3. Results: Obese boys had lower total testosterone (p