Estrogens and development

DES persistent alterations in expression of specific proteins

1987 Study Abstract

The normal development of the genital organs of mammals, including humans, is under hormonal control. A role for the female sex hormone estrogen in this process is still unclear. However, exposure of experimental animals or humans to the potent exogenous estrogen, diethylstilbestrol (DES), results in persistent differentiation effects. Since many chemicals in the environment are weakly estrogenic, the possibility of hormonally altered differentiation must be considered.

Experiments in mice that were treated with the synthetic estrogen, diethylstilbestrol (DES), demonstrated two salient features:

  1. the contralateral fetal genital duct system was retained into adulthood in both male and female offspring; in other words, DES-treated females retained both a female and male genital duct system as did treated males;
  2. and the ductal system consistent with the sex of the DES-treated mouse had numerous structural and functional defects along its length. For example, the Mullerian duct, which gives rise (starting cranially) to the oviduct, uterus, cervix, and upper vagina, had malformations of each of these organs in developmentally estrogenized females; moreover, functional defects including growth control derangements resulting in cancers are also seen in organs derived from the Mullerian duct.

Very similar defects are seen in women exposed in utero to DES. In fact, retention of Wolffian duct tissues as ovarian cysts, oviductal malformation, uterine abnormalities, and vaginal cancers have been reported in both species.

Thus, structural and functional defects are induced in the genital tracts of both species exposed to an exogenous estrogen during sex differentiation. The mechanism(s) underlying these defects are still not known. However, persistent alterations in expression of specific proteins can be demonstrated in the genital tracts of DES-treated mice. Thus, changes in the rate of cell/tissue differentiation, as well as induction of molecular defects within the target cell, are apparently involved.


  • Full study (free access) : Estrogens and Development, NCBI PubMed PMC1474430, Environmental Health Perspectives Vol. 75, pp. 25-27, 1987.
  • Featured image Ricardo Gomez Angel.

Have your say! Share your views