Clomiphene citrate does not modify the exaggerated thyrotrophin response to thyrotrophin-releasing hormone occurring in primary testicular failure.

Overview

Patients with primary testicular failure have increased basal TSH levels and an exaggerated TSH response to TRH in the presence of normal circulating levels of thyroid hormones. In order to evaluate it this TSH profile is an oestrogen-related phenomenon, sixteen patients with primary testicular failure were challenged with 200 micrograms TRH prior to and after the administration of clomiphene citrate. The latter was given in a dose of 100 mg/day for 4 weeks to ten patients; 200 mg/day for 4 weeks to three patients and 100 mg/day for 2 months to the final three patients. The patients demonstrated increased mean basal TSH levels with an exaggerated TSH response to TRH. Following the administration of clomiphene citrate, there were no changes in T4, T3 sephadex or total T3 levels and in basal or stimulated TSH levels. Clomiphene did produce an increase in oestradiol, testosterone, basal gonadotrophins and LH response to LHRH. Since the oestrogen antagonist, clomiphene citrate, had no effect on TSH secretion, it is unlikely that the exaggerated TSH response to TRH is mediated by oestrogens.