Conjugated estrogens

The conjugated estrogens are noncrystalline mixtures of purified female sex hormones obtained either by its isolation from the urine of pregnant mares or by synthetic generation from vegetal material. Both of these products are later conjugated to natrium sulfate by ester bonds in order to make them more water soluble.

The conjugated estrogen product contains a mix of estrogen from which about 50% is represented by estrone sulfate followed by 25% of equilin sulfate, 15% of 17-alpha-dehydroequilenin sulfate, 3% of equilenin sulfate, 5% of 17-alpha and 17-beta-dihydroequilenin sulfate, 2% of 17-alpha-estradiolsulfate and 3% of 17-beta-estradiolsulfate. It also presents a large number of unidentified molecules with weak estrogenic activity as well as non-human molecules when it is obtained from pregnant mares urine.

The conjugated estrogen mixture was approved for marketing in US in 1942 based on the efficacy against certain conditions. However, until 1986 official clinical trials were performed and this product was determined to be effective for the treatment of osteoporosis. The currently approved product of conjugated estrogens was developed by Wyeth Ayerst and FDA approved in 2003.

The conjugated estrogens are indicated for several different conditions including: