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Consumers Home > About DES > Known Health Effects > Known Health Effects for DES Sons
Known Health Effects for DES Sons

Known Health Effects

 Known Health Effects for Women Prescribed DES While Pregnant
 Known Health Effects for DES Daugthers
 Known Health Effects for DES Sons
This section addresses questions about increased health risks for DES Sons, including information on
  • non-cancerous epididymal cysts (growths on the testicles);
  • other genital abnormalities;
  • infertility;
  • ongoing follow-up studies;
  • steps for obtaining screenings and tests; and
  • what to tell your siblings about DES.
My mother was prescribed DES while pregnant with me. Am I at an increased risk for any health problems?

Only a few studies have focused on health problems experienced by men exposed to DES before birth (in the womb), known as DES Sons. The research has focused on the following health concerns among DES Sons.

  • Non-Cancerous Epididymal Cysts
    The most consistent research finding for DES Sons indicates that they have an increased risk for non-cancerous epididymal cysts, which are growths on the testicles (Bibbo, 1977; Gill, 1979; Conley, 1983; Niculescu, 1985; Wilcox, 1995). In one study, 21% of DES Sons had non-cancerous epididymal cysts compared with 5% of unexposed men (Gill, 1979).

  • Other Genital Abnormalities
    Whether DES increases the risk for other genital abnormalities in men remains unclear. A few studies have reported that DES Sons experience a greater likelihood of being born with undescended testicles (cryptorchidism), a misplaced opening of the penis (hypospadias), or a smaller than normal penis (microphallus). These studies estimated that 15%-32% of DES Sons experience one or more of these structural differences compared with 5%-8% of unexposed men (Gill, 1979; Wilcox, 1995). Other studies, however, have not identified an increased risk of structural differences (Leary, 1984; Vessey, 1983). Because findings have been inconsistent, researchers cannot say with certainty that DES causes these types of genital abnormalities in DES-exposed men.

  • Infertility
    DES Sons are not at an increased risk for infertility. Some DES Sons have been concerned that DES exposure might be linked to infertility. Although one study found a lower sperm count in men exposed to DES compared with unexposed men (Gill, 1979), a 40-year follow-up study of DES Sons found no increased risk of infertility among men exposed to DES before birth (Wilcox, 1995).
Are there any ongoing follow-up studies of DES Sons?

The National Cancer Institute's DES Combined Cohort Study began in 1992. This study follows men and women exposed to DES before birth (in the womb), known as DES Sons and Daughters, to monitor their health patterns compared with the general population. These cohort studies will continue to follow DES Sons regarding a range of health issues (such as cancer, heart disease, and autoimmune disease).

Cohort studies are designed to follow the same group of people over long periods of time. This means that new participants cannot be added to the study. To learn more about cohort studies, refer to Understanding DES Research: Role of Cohort Studies.

What steps should I take with my health care provider in terms of special screenings or tests based on my DES exposure?

Although no special screenings or tests are necessary for DES Sons, for more information tips are provided for working with your health care provider.

My younger brothers/sisters are worried that they were exposed to DES, even though my mom was only prescribed DES when she was pregnant with me. What can I tell them?

Only children who were in the womb at the time their mother was prescribed DES are considered to have been exposed to DES. To learn more about the increased health risks for DES Sons, refer to Recent DES Research and DES Bibliography.

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