US lists estrogens as carcinogens

All estrogens used in replacement therapies and contraceptives were listed Wednesday by the US government as ‘‘known human carcinogens,’’ a significant upgrading of the dangers they pose. However, government scientists said it is not yet known whether estrogens retain their cancer-causing potential when used in combination with other hormones, as they commonly are in hormone replacement therapy and in oral contraceptives.

This summer, a large clinical trial of hormone replacement therapy in post-menopausal women by the Women’s Health Initiative was halted early when it showed an increased incidence of breast cancer and heart disease. Many women stopped taking the medications. (LATWP)