The Plasma Gonadotropin Response to Gonadotropin-Releasing Hormone in Patients with Primary Hypogonadism

Synthetic gonadotropin-releasing hormone (LH/FSH-RH) was administered to 18 normal subjects (9 men and 9 women) and 14 patients with primary hypogonadism. The plasma LH response in the normal individuals was considerably greater than the plasma FSH response. While the release of both LH and FSH was accentuated in patients with primary hypogonadism, the plasma FSH response was more markedly increased in comparison to the response observed in normal subjects. It is suggested that FSH secretion may be more sensitive to feedback inhibition than LH secretion, and that the FSH response to LH/FSH-RH will be helpful in the diagnosis of patients with early gonadal failure.