Basal gonadotropin level and gonadotropin response to stimulation in patients with anorexia nervosa
Serum gonadotropin (GN) levels were examined before and after stimulation with luteinizing-hormone-releasing-hormone (LHRH) (100 micrograms/m2 body surface) in 25 female patients with anorexia nervosa (AN) and in 19 healthy young women. 12 patients were reexamined after clinical improvement. Basal GN levels and the luteinizing hormone (LH) response to stimulation were significantly lower in patients than in controls, whereas the response of follicle-stimulating hormone (FSH) to LHRH was normal. The GN response in patients was weight dependent, displaying an inverse correlation to the weight loss. After clinical improvement the GN response was significantly higher than in the acute stage of the disease. The data demonstrate that the activity of the hypothalamic-hypophyseal-gonadal (H-H-G) axis, evaluated on the basis of the GN response to LHRH, depends on the body weight of the patient. Hence, the alteration in activity of the H-H-G axis seems to be a consequence, and not the cause of AN.