Estrogens as a group often prescribed alone or in combination to re-establish optimal physiologic balance. (ERT). Estrogens are effective for the treatment of menopausal symptoms, the treatment of postmenopausal problems. They are also increase bone density, decrease improve heart health and decrease the incidence of colorectal cancer.

Conjugated equine estrogens, Premarin, are derived from pregnant mares’ urine; however, these are never naturally produced by humans. Research has shown that the risk of breast cancer is increased with the long term and the risk is further increased when the synthetic progestin Provera (medroxy-progesterone acetate) is added. The 2012 Hormone Therapy Position Statement of The North American Menopause Society.