Studies on ovarian and adrenal steroids at different phases of the menstrual cycle: IV. The effect of dexamethasone suppression and subsequent ACTH stimulation at different phases of the menstrual cycle and following the administration of 150 mg of depot-medroxyprogesterone acetate (DMPA)

Abstract

In an attempt to assess the effect of depot-medroxyprogesterone acetate (DMPA) on adrenal function, the peripheral levels of a variety of steroids were estimated after dexamethasone suppression and subsequent ACTH stimulation in 5 subjects. The steroid responses observed 16 and 54 days after a single injection of 150 mg of DMPA were compared with those obtained in the same women before DMPA treatment or with those found at different phases of the cycle in another group of 6 normally menstruating women. The levels of cortisol, pregnenolone, 17-hydroxypregnenolone, dehydroepiandrosterone, androstenedione and dihydrotestosterone were significantly suppressed by dexamethasone and stimulated by ACTH in all phases of the cycle, and before and after DMPA administration. The extent of suppression or stimulation (expressed as a percentage) was different in case of different steroids, but was rather constant with regard to the same steroid. Hence, the phase of the cycle or the administration of DMPA did not influence the functional capacity of the adrenal as reflected by the levels of these steroids. Dexamethasone administration did not exert any influence on the levels of progesterone and 17-hydroxyprogesterone during the different phases of the cycle; however, ACTH administration increased the levels of these two steroids in the follicular phase and also after DMPA treatment. The levels of estradiol and lutropin were not influenced by dexamethasone or ACTH at any of the occasions studied. It is concluded that the functional capacity of the adrenal cortex is constant during the various cycle phases and is not affected by the administration of a single dose of 150 mg of DMPA.