Low Exposure to Organochlorines, Mercury Affects Thyroid During Pregnancy

According to researchers, exposure at lower levels to polychlorinated biphenyls ( PCBs ), particular pesticides, and mercury can interfere with thyroid hormone levels during pregnancy. The study looked at the effects of low environmental exposure to thse toxins during pregnancy.

The study looked at volunteers from their first prenatal vist, throughout their pregnancy and delivery. The researchers found that there was a significant inverse relationship between total T3 blood levels in pregnant women and low environmental exposure to various pollutants. The greater the exposures, the lower the T3 levels were. Adequate T3 levels are necessary to maintain a healthy pregnancy and baby.

Study coauthor Larissa Takser, of Laboratoire de Physiologie Materno-foetale, Montreal, said: "Our findings place emphasis on the need to be more vigilant in regard to particularly fragile populations such as pregnant women and fetuses."

More Information

For more information about thyroid disease during pregnancy...

Pregnancy & Thyroid Disease Information Center

Thyroid Guide to Pregnancy Fertility & Breastfeeding Success

Source: Environmental Health Perspectives, National Institute of Environmental Health Sciences, part of the U.S. Department of Health and Human Services, 2005