Response of plasma LH and FSH to synthetic LH-RH in children at various pubertal stages.

Fifty normal boys and 47 normal girls, aged 5 to 18 years, underwent a standard luteinizing hormone-releasing hormone (LH-RH) test (50 mug/sq m by rapid intravenous injection), and the plasma levels of LH and follicle-stimulating hormone (FSH) were determined. The results were analyzed separately according to the pubertal stages for each sex. A wide range of distribution of the individual measurements of the plasma gonadotropins throughout the LH-RH tests was found, but the mean values of the basal and peak levels showed a definite pattern for each sex at the different pubertal stages. Of particular interest was the sharp rise in basal plasma FSH level and its marked response to LH-RH in girls at the onset of puberty. The girls at this stage had the highest basal and peak FSH levels obtained at any pubertal stage in both sexes. It is concluded that the establishment of norms of LH and FSH response to a standard dose of LH-RH will be useful in evaluating normal and abnormal pubertal states in both sexes.