Endocrine-disrupting chemicals (EDCs) in the environment may be disrupting women’s reproductive systems, including their ovaries, and leading to early menopause, according to a recent Washington University study.
These chemicals have been shown previously to interfere with reproductive hormone metabolism; this is the first study to demonstrate the potential effects on ovarian reserve.
“Phthalates and PCBs (polychlorinated biphenyls), which humans are exposed to through diet, personal care products and plastics, are associated with an earlier onset of menopause,” says lead author Amber Cooper, MD, a Washington University reproductive endocrinology and infertility subspecialist at Barnes-Jewish Hospital who has both clinical and research interests in ovarian aging. “This study is another step in helping to explain the mechanisms behind that association.”
Cooper and her colleagues presented the findings Nov. 5, 2012, at the annual meeting of the American Society for Reproductive Medicine.
The researchers looked at the levels of numerous EDCs in the blood or urine of 5,700 women through a secondary analysis of the US National Health & Nutrition Examination Survey (NHANES) database. Those with the highest amounts of phthalates and PCBs went through menopause an average of 2.5 years before the others. The average age of menopause in the US is 51.
Potentially detrimental effects
“Our research is preliminary, but this is enough evidence to show that high levels of these chemicals may have a detrimental effect in the long term and warrant future research,” Cooper says.
Early menopause has been linked to increased incidence of fatal brain hemorrhages, heart disease, strokes and bone density problems.
Although scientists are not sure why some women have higher levels of these chemicals, exposure from make-up, hair spray or packaged food may be to blame.
More research is needed to better understand these mechanisms, Cooper says. She and her team currently are studying a larger sampling of women and nearly 120 individual chemicals that could have an environmental impact on ovarian health.