- By Liza Torborg
Mayo Clinic Q and A: Women Should Talk to Doctor About Possible Health Risks if Exposed to DES in Utero
ANSWER: There is no evidence to show that using vaginal estrogen cream raises the cancer risk of women with diethylstilbestrol, or DES, exposure in utero. However, it’s a good idea to talk with your doctor about your DES exposure before you use any type of hormone replacement therapy or oral contraceptives. If you haven’t already done so, you should also discuss with your doctor the other possible health risks associated with DES exposure.
DES is a synthetic form of the female hormone estrogen. From the 1940s through the 1960s, DES was prescribed to pregnant women to prevent miscarriage, premature labor and other pregnancy complications.
In 1971, researchers linked DES exposure before birth to a rare form of cancer that affects the cervix and vagina, called clear cell adenocarcinoma. Soon after that study was published, physicians stopped prescribing DES to pregnant women. Additional research revealed that DES can cause problems in the body’s endocrine system. In women whose mothers took DES when they were pregnant, that may raise their risk for a variety of medical concerns.
For example, those women are about 40 times more likely to develop clear cell adenocarcinoma than women who were not exposed to DES in the uterus. But that cancer is very rare, so the number of DES-exposed women who get it is still quite low. This group’s risk for breast cancer also is slightly increased. No other cancer risk appears to be increased for women with DES exposure. But research into this topic is still ongoing.
Other possible complications from DES exposure may include an increased risk for development of abnormal cells in the cervix and vagina, which can be detected with Pap smear screening. These cells are not cancerous, but they could eventually lead to cancer if they are not detected and treated.
Structural changes in the cervix, vagina and uterus are more common in women exposed to DES in utero. These changes may result in the cervix, vagina or uterus having an unusual shape. In some cases, that can make it difficult to become pregnant or to carry a healthy pregnancy to full term. Other problems related to pregnancy in DES-exposed women include tubal, or ectopic, pregnancies, miscarriages and a serious condition that can develop during pregnancy called preeclampsia.
Because these health concerns are all linked to exposure to an artificial estrogen as a fetus, some physicians have cautioned women who were exposed to DES to avoid other forms of estrogen, too, including hormone replacement therapy and oral contraceptives. No research has shown, however, that there’s a link between these kinds of estrogen — which would include vaginal estrogen cream — and an increase in additional health risks.
That said, it is important for you to discuss any concerns you have about your DES exposure with your doctor. He or she can help you assess your overall risks and make recommendations for screening exams and other follow-up care based on your individual needs. Women exposed to DES may be advised to have more frequent Pap smears to look for cell changes in the cervix and vagina, for example. Treatment for infertility may be recommended sooner than usual for women with DES exposure, and increased monitoring during pregnancy may also be recommended. — Dr. Mary Gallenberg, Obstetrics and Gynecology, Mayo Clinic, Rochester, Minn.