Gonadotropin profiles in fed and fasted obese women.

Five obese women were studied before and at the end of a prolonged fast to determine the effect on luteinizing hormone (LH) and follicle-stimulating hormone (FSH) and on the response to luteinizing hormone--releasing factor (LRF). Although baseline serum LH values declined from a mean value of 9.1 to 6.5 m.I.U. per milliliter measured at the end of the fast, these changes in mean serum level were not statistically significant. However, the integrated LH secretion did decline when measured at the end of the fasts (p less than 0.05). FSH secretion did not change. LRF-stimulated LH and FSH values showed augmented stimulation at the end of the fast. Pulsatile gonadotropin secretion patterns remained normal. Prolonged fasting appears to alter the baseline LH secretion and the pituitary response to exogenous LRF.