Estrogen Safety: Studies raise cancer, blood clot questions

Three studies this week brought mixed news about the risks of estrogen-only hormone replacement therapy to ameliorate menopausal symptoms.

Data from a massive study called the Women’s Health Initiative (WHI) show that estrogen therapy taken for 7 years doesn’t increase a woman’s risk of breast cancer. However, a separate study of black women finds a greater risk of breast cancer in women who took the hormone for 10 or more years than in women who had no hormone therapy.