Transdermal estradiol in the treatment of postmenopausal bone loss

Abstract The effects on calcium metabolism and forearm bone mineral density of sequential transdermal estradiol (ESTRADERM TTS-50), 50 μg/day and medroxyprogesterone (10 mg/day for 12 days) was studied in a randomised controlled trial in 34 healthy females 2–4 years after the menopause. At the end of the 18 months' treatment course with transdermal estradiol, bone density was increased by 4.31% ( P P In conclusion, small doses of transdermal estradiol are as effective as oral estrogens. This suggests that the bone sparing effects of estrogens may be due only to low circulating estradiol concentrations, but not to supraphysiological estrone levels. It seems also that estrogens exert both a straight inhibition of bone resorption and a partial inhibition of parathyroid responsiveness.