Diethylstilbestrol (DES) and cancer

Diethylstilbestrol (DES) is a synthetic form of the female hormone oestrogen first manufactured in 1938. It was prescribed in Australia in the late 1940s and 1950s, less often in the 1960s and 1970s, and was prescribed in some instances beyond 1971.

DES was primarily given to prevent miscarriage and other pregnancy complications, such as tubal pregnancy and early delivery.

Other therapeutic uses included suppression of lactation and treatment of post-menopausal syndrome.

Who was exposed to diethylstilbestrol?

• DES mothers – women who took DES while pregnant
• DES daughters and sons whose mothers took DES while they were pregnant with them.

DES and negative health effects

Although the majority of people exposed to DES will not experience any negative health effects, available research findings indicate that exposure to DES increases the risk of a number of health problems.

Adverse health effects of DES for women

Women who took DES during pregnancy have a small increased risk for breast cancer.

Women exposed to DES in utero (DES daughters) are at increased risk of:

• breast cancer – (for women over 40)
• clear cell adenocarcinoma of the vagina/cervix
• structural abnormalities in the reproductive tract
• miscarriage
• tubal (ectopic) pregnancy
• infertility
• premature birth.

Adverse health effects of DES for men

Men exposed to DES in utero (DES sons) are at increased risk of:

• abnormally small testes
• undescended testes
• non-cancerous epididymal cysts.

Adverse health effects for DES grandchildren

Research into the health of DES grandsons and granddaughters has not found conclusive evidence of an increased cancer risk except for the possibility of a heightened ovarian cancer risk in DES granddaughters.

Continued monitoring of the third generation of individuals whose grandmothers were exposed to DES during pregnancy is needed to conclusively determine whether there is an increased risk of cancer in this population group.

Managing the risk

Relevant health care providers such as general practitioners, midwives and women’s health nurses who are familiar with DES can assist people affected by DES to identify possible complications.

Mammograms

Women prescribed DES while pregnant and DES daughters who are over 40 are advised to follow normal screening recommendations for their age group.

They should also be breast aware by familiarising themselves with the normal look and feel of their breasts, and report any unusual breast changes to their doctor, irrespective of both the time since their most recent mammogram and the results of that mammogram.

Cervical screening

Women exposed to DES in utero are advised to have a cervical screening co-test and colposcopy annually. A co-test looks for the presence of human papillomavirus (HPV) as well as abnormal cervical cells.

Daughters of DES exposed women should screen every 5 years, consistent with national policy. However, if these women have concerns, more frequent screening could be offered on an individual basis.

For more information about cervical screening and DES visit the Cancer Council Australia cancer guidelines – cervical cancer screening chapter 17 Screening in DES-exposed women (external site).

Pregnancy

DES daughters planning pregnancy should alert their clinician of DES exposure prior to conception so they can be evaluated for cervical and uterine abnormalities.

During pregnancy, DES daughters should be treated as high risk patients.

Checks for men

DES sons should regularly check for lumps or swellings on the surface of the testes and promptly report any testicular masses, blood in the urine, or genital complaints to their doctor.

Remember

• Diethylstilboestrol (DES) was commonly prescribed from 1946 to 1971 to prevent:
  • miscarriages
  • early birth delivery
  • ectopic pregnancy.
• DES can cause changes to the male and female reproductive system.
• DES daughters:
  • should have an annual DES examination
  • over 40 should follow normal screening mammogram recommendations for their age group and be breast aware
  • have a slightly increased risk of infertility
  • have higher risk of pregnancy complications.

This information provided by

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