Abstract
In an attempt to elucidate the mechanism of suppressive action of glucocorticoids
on the hypothalamo-pituitary-ovarian axis, we studied the effects of short-term high
dose dexamethasone administration on the LH and FSH responses to LHRH and to clomiphene
in healthy women with normal menstrual cycles. Seven women, 21-35 years of age, received
100 /µg of LHRH i.v. on day 6 of two consecutive menstrual cycles, once with and once
without pre-treatment with dexamethasone 2 mg orally every 6 hrs. on days 2 through
5 of the menstrual cycle. Seven other women (ages 21-35 years) received clomiphene
citrate 100 mg on days 2 through 5 of their menstrual cycle, once with and once without
simultaneous administration of dexamethasone 2 mg orally every 6 hrs. The administration
of dexamethasone suppressed baseline serum levels of LH and FSH and blunted LH and
FSH responses to both LHRH and clomiphene. The results indicate that short-term administration
of pharmacological doses of glucocorticoids suppress the secretion of LH and FSH by
a direct effect on the anterior pituitary and possibly by an effect at the hypothalamic
level with inhibition of the release of LHRH.
Key words
LHRH - Clomiphene - Gonadotropins - Glucocorticoid Suppression