Benefits and risks of estrogen replacement therapy.

Estrogen replacement therapy (ERT) has been shown to reduce the risk of cardiovascular disease (CVD) and osteoporosis in postmenopausal women. Studies also indicate a reduced risk of stroke and its consequent mortality among estrogen users, and ERT may also have a role in reducing the risk of Alzheimer's disease and increasing a woman's overall quality of life. On the negative side, some studies show a small duration-related risk of breast cancer with estrogen use and a significant increase in endometrial cancer; the latter is virtually eliminated with the addition of a progestin to the regimen. Although the definitive answer is not yet available, recent epidemiologic data suggest no reduction in protection against CVD and bone fracture with the addition of progestin, which is referred to as hormone replacement therapy, as opposed to using estrogen alone. A woman's potential risks associated with ERT or hormone replacement therapy must be weighed against her lifetime risks of developing CVD, stroke, and bone fracture. The reduction in mortality and morbidity rates with hormone use is generally viewed to be substantial and cost-effective. Health care professionals have an important role in shaping their patients' attitudes. Patients need more information from their physicians about the risks and benefits of estrogen therapy.