Diethylstilbestrol revisited: a review of the long-term health effects

* Purpose: To review the literature on the long-term health effects of exposure to diethylstilbestrol (DES) among women prescribed DES during pregnancy (DES mothers), among their children exposed in utero to the drug (DES sons and daughters) and among the progeny of these exposed sons and daughters (DES grandchildren). * Data Sources: English-language articles were identified through MEDLINE and CANCERLIT searches and through review of the bibliographies of identified articles. * Study Selection: All human studies relevant to long-term health effects of exposure to DES were reviewed. * Data Extraction: Descriptive data on existing DES cohorts were extracted from early publications. Risk estimates for health effects were extracted from published reports. * Data Synthesis: An estimated 5 to 10 million Americans received DES during pregnancy or were exposed to the drug in utero. Exposure to DES has been associated with an increased risk for breast cancer in DES Mothers (relative risk, * Conclusions: Further research is needed to define long-term health effects related to DES exposure. Such research would provide a basis for counseling persons exposed to DES and would further understanding of environmental and pharmacologic compounds similar to DES.
Studies document serious long-term adverse effects in women who took diethylstilbestrol (DES) during pregnancy and in their daughters and sons. Women who took DES have about twice the risk of breast cancer compared with unexposed women. Women exposed to DES in the womb have a risk of between 1 in 1,000 to 1 in 10,000 between birth and age 34 for cervico-vaginal clear-cell adenoma, an extremely rare cancer. Abnormal cervical and vaginal cells are frequently observed, but the connection with cancer is unknown. One study found 3.6 times the risk of ovarian cancer. DES daughters often have developmental abnormalities of the reproductive tract, and they are more likely to be infertile and to have ectopic pregnancies, miscarriages, and preterm births. One study showed an increased lifetime risk for autoimmune disease. DES sons may have an increased risk of testicular cancer and urogenital abnormalities.