Assessment of gonadotrophin secretion in women with anorexia nervosa

The LH and FSH secretions in 21 patients with anorexia nervosa were assessed by radioimmunoassay. On a single iv injection of 100 mug LH-releasing hormone (LH-RH), 8 patients showed LH response comparable to that of normal cyclic women in the follicular phase, and 5 patients showed excessive response. Although the remaining 8 patients showed almost no LH response, infusion of 400 mug LH-RH or daily im injections of LH-RH restored gonadotrophin responsiveness to LH-RH in all patients tested. The initial rise in LH during clomiphene citrate treatment was observed in 3 out of 5 patients, but the second peak of LH was found in only one patient. The initial suppression of LH following iv injection of conjugated oestrogen (Premarin) was observed in 9 out of 10 patients but a rebound increase comparable to that in normal cyclic women in the mid-follicular phase was found in only 3 patients. These results seem to suggest that impaired hypothalamic function is the cause of gonadotrophin deficiency and the resultant anovulation in most patients with anorexia nervosa.