Acute effects of intravenous infusion of conjugated estrogen on serum levels of LH and FSH in post-menopausal and castrated women.

In order to quantify the changes of feed-back effect of estrogen on the release of pituitary gonadotropin which is regulated by the hypothalamic-pituitary-ovarian system, the responses of LH and FSH to the intravenous infusion of 20 mg of conjugated estrogen were studied in 49 post-menopausal and 20 castrated women. In the group of women within 1 year after menopause, serum LH levels were elevated following the infusion of the conjugated estrogen. The responses of serum LH and FSH levels were different between post-menopausal and castrated women. The data indicated that the difference between the two groups was probably due to the difference of secrection patterns of the gonadotropins in post-menopausal and castrated women.