NEW YORK, Oct 02 (Reuters) -- Like the daughters of women who took DES (diethylstilbestrol) during pregnancy, the granddaughters of these women may also have an increased risk of reproductive tract cancers, according to researchers at the National Institute of Environmental Health Sciences (NIEHS), a division of the national Institutes of Health.
DES, a synthetic estrogen, was used to treat women at risk for miscarriage for more than 20 years until 1971, when investigators began to find rare reproductive tract cancers in the young daughters of the treated women.
Now, studies of mice indicate that the next generation of women, the granddaughters, may also have a higher risk for certain cancers, including cancer of the uterus.
However, while both generations of mice had increased risk of reproductive tract cancers, fertility was impaired only in the female mice exposed to DES in utero (the ``DES daughters''), not in their unexposed female offspring (the ``DES granddaughters''), according to the researchers.
Retha Newbold and fellow scientists at the NIEHS in Research Triangle Park, North Carolina, Wake Forest University in Winston-Salem, and Tulane University in New Orleans, Louisiana, said their data suggest ``transmission of susceptibility of genital tract cancer to subsequent (unexposed) generations.'' They said this concept is supported by results in male mouse siblings. In them, as in the females described in the study, reproduction is not affected, but rare cancers are observed. A report on the effects in males is being completed.
The scientists said their findings support and confirm data from other studies that report the transgenerational effects of DES.
``While the occurrence of reproductive tract tumors in DES lineage mice does not predict a similar outcome in DES-exposed humans, continued close surveillance of the prenatally DES-exposed (mice) and their offspring is warranted,'' the authors write.
``These results indicate that the cascade of
events that lead to the appearance of tumors may well begin
before birth and perhaps before conception,'' they add.