Increased Release of LH After Administration of LH-RH to Men Pretreated With Clomiphene

LH-releasing hormone (LH-RH) was administered to 6 men who had been pretreated with clomiphene citrate (200 mg/day) for 8 or 16 days. The ingestion of clomiphene for 8 days resulted in a significant rise in serum LH and FSH levels which did not further increase to a statistically significant extent after another 8 days. Injection of 0.7 mg of highly purified porcine LH-RH on the 8th or 16th day induced a further significant increase in serum LH (141%) and serum FSH (38%). The response to LH-RH, which reached a peak between 16 and 32 min after iv injection, did not differ significantly between the men taking clomiphene for 8 days and those taking it for 16 days. The results demonstrate that LH-RH can further increase the release of LH in subjects whose LH levels already have been elevated by the ingestion of clomiphene.