DES is a synthetic compound that has the properties of natural estrogens. Estrogens are hormones that are important in the development and regulation of the female reproductive system. They are produced primarily by the ovaries during a woman’s childbearing years. DES is an abbreviation for the compound’s chemical name, diethylstilbestrol.
Beginning in the 1940’s, physicians in the United States prescribed DES to as many as 5 million pregnant women threatened with miscarriages. It was believed that DES helped prevent miscarriages, but later studies failed to support this belief. Furthermore, research revealed that daughters of mothers treated with DES have an increased risk of developing cancer of the cervix or vagina. The cervix and vagina are parts of the female reproductive system. There is also some evidence that daughters of mothers who used DES may have structural abnormalities of the sex organs, causing fertility and pregnancy problems. Other studies have shown that sons of mothers who used DES may have structural abnormalities of the urinary system and sex organs. In 1971, the United States Food and Drug Administration (FDA) withdrew its approval for the use of DES during pregnancy.
For many years, farmers in the United States used DES to increase the growth and size of cattle and sheep. In 1979, the FDA banned the use of DES in animal feed because some of the compound remained in the meat.
Today, DES is occasionally prescribed as a treatment for cancer of the prostate gland, a male reproductive organ. It is also sometimes used to treat breast cancer in women who have reached the end of their natural childbearing years and in men.
