The Effect of Estrogen Dose on Postmenopausal Bone Loss

Abstract

In order to establish whether the favorable effect of estrogen therapy on postmenopausal bone loss was dose related, we measured sequential changes in the cortical diameters of the metacarpals by radiographic morphometry in 120 normal postmenopausal women who were being treated with ethinyl estradiol in doses ranging from 5 to 50 μg daily. There was a net loss of bone at doses below 15 μg per day and a net gain at doses of 25 μg per day and above. At doses between 15 and 25 μg daily, bone was neither gained nor lost.