Hormone replacement therapy (HRT) has been the method of choice for th
e prevention of postmenopausal osteoporosis since the early 1990s, Alt
hough a number of routes of administration are now available, HRT is s
till predominantly administered orally, In the United States, HRT form
ulations traditionally comprise conjugated equine estrogens, In Europe
, however, HRT preparations tend to be based on 17 beta-estradiol, a n
atural human estrogen, Furthermore, distinct patterns of HRT use are a
pparent based on the age of the woman receiving it, Current recommenda
tions are that early postmenopausal women (in their early 50s) receive
sequential combined estrogen/progestogen therapy with continued month
ly bleeds, while in women who are at least 1 year postmenopausal, cont
inuous combined HRT, which leads to endometrial atrophy and cessation
of monthly bleeding, is preferred, Clinical experience to date clearly
demonstrates that long-term HRT unequivocally increases bone mass and
reduces the risk of fractures in postmenopausal women, with no signif
icant differences between sequential and continuous combined prescribi
ng regimens, Data demonstrating that antiestrogens such as tamoxifen m
ay preserve bone mass have led to the initiation of large-scale trials
to determine the potential clinical utility of such agents for the pr
evention of osteoporosis in postmenopausal women, Nonhormonal therapeu
tic approaches are now also available, most notably bisphosphonates an
d vitamin D analogs, At present, however, traditional HRT remains the
regimen of choice for the prevention of postmenopausal osteoporosis, g
iven its additional beneficial effects on acute menopausal symptoms, a
s well as on the cardiovascular system and brain. (C) 1996 by Elsevier
Science Inc.