WEDNESDAY, May 2, 2018 (HealthDay News) -- Women who were exposed to synthetic estrogen (DES) in the womb and developed a rare form of cancer of the vagina and cervix continue to face an increased risk of death, a new study shows.
DES was once commonly given to pregnant women because it was believed it could prevent miscarriage and preterm birth.
However, the U.S. Food and Drug Administration issued a warning in 1971 that DES was linked with a rare cancer of the vagina and cervix in female children of women who took the drug during pregnancy.
In this latest study, University of Chicago researchers found that DES-exposed women with clear-cell adenocarcinoma had high rates of death throughout their life span.
"The risk of death for women aged 10 to 34 who had been exposed to DES in utero [in the womb] and had clear-cell adenocarcinoma was 27 times higher than the risk for women in the general U.S. population," study author Dr. Dezheng Huo, an associate professor of public health sciences, said in a university news release.
And the risk lingered as these women aged: It was five times higher among women aged 35 to 49 (mainly due to late recurrences of their cancer), and two times higher among women aged 50 to 65, the findings showed.
In the 25 years before the first eight cases of clear-cell adenocarcinoma associated with DES were identified, about 4.8 million U.S. women and as many as 10 million worldwide had taken DES during pregnancy, the study authors noted.
By 2014, researchers had identified about 700 patients with the cancer who had a 20-year survival rate of 69 percent due to early diagnoses and aggressive surgery.
The investigators also found that women who took DES appear to be at increased risk for breast cancer, while women exposed to DES in the womb showed an increased risk of breast cancer after age 40.
The University of Chicago researchers said the increased risk of premature death among women older than 50 "emphasizes the importance of other life-threatening health conditions in later life of the DES population."
The findings were outlined in a letter published in the May 3 issue of the New England Journal of Medicine.
The U.S. National Cancer Institute has more on DES.