(dī-ĕth‵ĭl-stĭl‵bĕs'trŏl )

ABBR: DES

A synthetic preparation possessing estrogenic properties. It is several times more potent than natural estrogens and may be given orally. It is used therapeutically in the treatment of menopausal disturbances and other disorders due to estrogen deficiencies.

Diethylstilbestrol should not be administered during pregnancy. Such use has been found to be related to subsequent vaginal malignancies in the daughters of mothers who were given it.

This drug was once used extensively during pregnancy to treat threatened and habitual abortion. An estimated 5 million to 10 million Americans received DES during pregnancy or were exposed to the drug in utero. Those who were exposed to DES in utero were found to be at risk of developing reproductive tract abnormalities such as clear-cell cervicovaginal cancer in women and reproductive tract abnormalities in men. These findings were reported in 1970; the use of the drug during pregnancy was subsequently banned in the U.S. in 1971 and in Europe in 1978. Women who took the drug are now known as DES mothers and their daughters and sons are known as DES daughters and DES sons, respectively.

SEE: daughter, DES; DES syndrome.