Integration of pulsatile gonadotropin secretion by timed urinary measurements: an accurate and sensitive 3-hour test

The integration of pulsatile gonadotropin secretion by the radioimmunoassay of an acetone precipitation from a short-term urine sample was evaluated. FSH and LH excretion over a 3-h period was compared to the mean level of 10 blood samples obtained every 20 min for a similar time period from 71 patients. A highly significant correlation existed between blood and urine results. In addition, the gonadotropin levels obtained from a 3-h sample correlated well with the 24 h excretion of FSH and LH from the same individual. A 3-h urine collection can provide a simple, sensititve, and accurate means of assessing circulating FSH and LH levels.