Diethylstilbestrol
Diethylstilbestrol (DES), a nonsteroidal (i.e., not of the class of steroid molecules) estrogen first synthesized in 1938, was believed to prevent miscarriages in women until a 1953 randomized controlled trial proved it did not.
Safety
A 1971 study established that it increased in utero cancer risks for fetuses whose mothers had taken it during pregnancy. In response, the U.S. Food and Drug Administration banned its use in pregnancy.
In the United States, it is manufactured only for research and veterinary use. [1]
It is banned in much of the world, but new cases of its use in pregnancy continue to surface.
Women who took DES
Patients who took it are at slightly increased risk of developing breast cancer.
Daughters of women who took DES in pregnancy
In women whose mothers took DES during pregnancy, it increased risk of:
- Clear cell adenocarcinoma (CCA) of the vagina and cervix
- Reproductive tract structural differences
- Pregnancy complications
- Infertility
Sons of women who took DES in pregnancy
Men whose mothers who took DES are at an increased risk for epididymal cysts.
Other indications
DES has been prescribed for the treatment of advanced breast and prostate cancer.