Monday, May 14, 2007

Exposure to bisphenol A is associated with recurrent miscarriage

Sugiura-Ogasawara, M, Y Ozaki, S Sonta, T Makino and Kaoru Suzumori 2005. Exposure to bisphenol A is associated with recurrent miscarriage. Human Reproduction 20:2325-2329.

In 2003, Hunt et al. reported that bisphenol A causes meiotic aneuploidy in mice. This report stimulated concern and speculation about its relevance to humans, because meiotic aneuploidy is the largest known cause of spontaneous miscarriage in people and because human exposure to bisphenol A is so widespread, thanks to its use in consumer products. The exposure level sufficient to cause the effect in mice was within the range people experience in the general population.

With this study, Sugiura- Ogasawara et al. provide the first, indication that BPA is associated with recurrent miscarriage in people, as predicted by Hunt et al.'s results. They found higher levels of BPA in women with a history of recurrent miscarriage, and evidence of meiotic aneuploidy in their miscarried fetuses.

This is the second study to be published within a month to test the impacts of endocrine disrupting chemicals in people based on animal studies. Just two weeks ago, Swan et al. showed a highly significant relationship between elevated phthalate levels and genital abnormalities in boys, as predicted by work on rodents.

Skeptics of human impacts of EDCs have repeatedly claimed that 'we have decades of experience with X or Y and there is no evidence of harm in people.' The flaw in that argument is that the relevant human studies haven't been done; they are confusing absence of data with proof of safety. Now that epidemiologists are using animal data to guide their research, we have direct contradictions of those assertions.


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