To critically review the risks and benefits of hormone therapy for asymptomatic postmenopausal
women who are considering long-term hormone therapy to prevent disease or to prolong
Review of the English-language literature since 1970 on the effect of estrogen therapy
and estrogen plus progestin therapy on endometrial cancer, breast cancer, coronary
heart disease, osteoporosis, and stroke. We used standard meta-analytic statistical
methods to pool estimates from studies to determine summary relative risks for these
diseases in hormone users and modified lifetable methods to estimate changes in lifetime
probability and life expectancy due to use of hormone regimens.
There is evidence that estrogen therapy decreases risk for coronary heart disease
and for hip fracture, but long-term estrogen therapy increases risk for endometrial
cancer and may be associated with a small increase in risk for breast cancer. The
increase in endometrial cancer risk can probably be avoided by adding a progestin
to the estrogen regimen for women who have a uterus, but the effects of combination
hormones on risk for other diseases has not been adequately studied. We present estimates
for changes in lifetime probabilities of disease and life expectancy due to hormone
therapy in women who have had a hysterectomy; with coronary heart disease; and at
increased risk for coronary heart disease, hip fracture, and breast cancer.
Hormone therapy should probably be recommended for women who have had a hysterectomy
and for those with coronary heart disease or at high risk for coronary heart disease.
For other women, the best course of action is unclear.