Are the anterior pituitary-like substances gonadotropic?

Twelve patients with a normal menstrual rhythm were given 500 R.U. of antuitrin-S daily for four or six weeks. The majority of these patients did not show any significant alteration in rhythm. Five (42 per cent) experienced an amenorrhea of from one to five months following treatment. This induced amenorrhea was accompanied by a progressive atrophy of the endometrium, indicating a suppression of ovarian follicles. Antuitrin-S failed to establish uterine bleeding in patients with amenorrhea. No evidence of ovulation or luteinization, as demonstrated by a secretory endometrium, was found. On the basis of this experiment it appears that the anterior pituitary-like substances are not gonadotropic in the human female and in sufficient dosage may even be gonadotoxic.