Columbia: A study by researchers at Columbia University’s Mailman School of
Public Health and Harvard T.H. Chan School of Public Health reports
elevated odds for attention deficit hyperactivity disorder (ADHD) in the
grandchildren of users of diethylstilbestrol, a synthetic estrogen
commonly known as DES which was prescribed between 1938 and 1971 to
prevent pregnancy complications. This is the first study to provide
evidence of the potential neurodevelopmental consequences of DES use
across generations. The findings are published online in JAMA Pediatrics.
DES
treatment for pregnant women was phased out after a 1953 study showed
no benefit, and was banned in 1971 when DES was linked to vaginal
adenocarcinomas in the daughters of women who had used DES during
pregnancy. DES, which disrupts the body’s endocrine system, was later
also linked to multiple other reproductive problems in DES daughters.
Although the exact number of pregnant women that used DES is unknown, in
the U.S. it is estimated to be between 5–10 million.
“Our aim was
to explore the potential impact of DES use across generations, and
specifically on third-generation neurodevelopment,” said Marianthi-Anna Kioumourtzoglou, ScD, assistant professor of Environmental Health Sciences
at the Mailman School of Public Health. “To date, and to our knowledge,
no epidemiologic study has assessed multigenerational impacts of DES—or
any other endocrine disruptors—on neurodevelopment.”
The study
was based on self-reported health information from 47,540 participants
enrolled in the ongoing Nurses’ Health Study II, approximately 2 percent
of whom had mothers who used DES while pregnant, as well as the 106,198
children born to nurses in the study.
Using DES was associated
with 36 percent higher odds of ADHD among grandchildren of women who
used DES compared to grandchildren women who did not use the drug during
pregnancy. These results did not differ by the sex of the children.
“While
DES is banned, pregnant women continue to be exposed to a large number
of environmental endocrine disruptors,” said Marc Weisskopf, PhD, ScD,
professor of Environmental and Occupational Epidemiology at the Harvard
T.H. Chan School of Public Health, and senior author of the study. “And
although current exposures are at a lower level and potency than seen
with DES, cumulative exposures to these chemicals may be cause for
concern and is deserving of further study.”
Co-authors are Brent
Coull, Harvard T.H. Chan School of Public Health; Éilis O’Reilly, School
of Public Health and Epidemiology, University College Cork, Ireland;
and Alberto Ascherio, Harvard T.H. Chan School of Public Health, and
Brigham and Women’s Hospital, Boston.
The study was supported by
the National Institutes of Health (ES007069, ES000002, ES009089,
CA176726), and the Escher Fund for Autism.