Estrogens in prevention and treatment of osteoporosis.

The osteoporosis is a common problem among postmenopausal women causing at least 1.5 million fractures each year in the USA. Osteoporotic fractures are also common in women with other hypo-estrogenic states. Bone mass among females is fairly constant until the 5th decade and then begins to decline at all skeletal sites. This fall coincides with the gradual onset of ovarian failure. We were able to demonstrate reduced bone mass within three years of oopharectomy, but not in hysterectomized women with intact ovarian function. Estrogen therapy has been shown in a variety of studies to prevent the loss of bone that follows menopause. Cessation of therapy results in restoration of bone loss. The use of estrogen preparations in women with intact uterus requires the addition of a progestogen to protect against the deleterious long-term effects of unopposed estrogen on the endometrium. This does not interfere with the effects of estrogens on the skeleton, but does result in the return of menses, which reduces compliance among the older female population. In our group estrogens are usually prescribed orally (0.625 mg Premarin or its equivalent, or by another route (percutaneous transdermal), provided estradiol levels can be maintained in the modfollicular range. Estrogens are given continuously and- for women with intact uterus--a progestogen is added (Provera 5 mg per day) for 12-14 days each month, starting on the first day of each calendar month. All women should be followed by a gynecologist and have mammography appropriate to their age range. Reduced bone mass at the time of menopause probably indicated an individual who is at increased risk of osteoporosis and should be treated. As alternatives to estrogens calcitonin and diphosphonates can be prescribed to women who do not wish to take estrogen treatment.