Estrogen replacement in menopausal women: recent and current prospective studies, the WHI and the KEEPS

In the wake of the Women's Health Initiative (WHI) trials, many questions have yet to be resolved regarding the use of hormone replacement therapy (HRT) in postmenopausal women, primarily whether HRT's cardioprotective effects outweigh a possible increase in breast cancer risk. Several factors, including differences in HRT regimens, the duration of follow-up, and study participants' ages, may have contributed to the widely different conclusions of the WHI trials in comparison to the observational studies. A woman's risk of dying from heart disease is roughly 10 times greater than her risk of dying from breast cancer. Soon after menopause, the rate of heart disease accelerates rapidly, whereas the rate of breast cancer increases slowly. Estrogens have been found to reduce coronary heart disease and to have favorable effects on lipid profiles. The risks of adverse health effects must be balanced against the benefits associated with HRT Further research into the timing of estrogen replacement treatment may be crucial to the prevention of cardiovascular disease.