Jodi Flaws, Ph.D.
University of Illinois, Urbana-Champaign
NIEHS Grants P01ES022848, P20ES018163
A study, funded in part by NIEHS, found an association between low levels of BPA exposure during pregnancy and reproductive problems in the next three generations of mice. The new findings suggest that some effects of in utero BPA exposure, including ability to become pregnant and to maintain pregnancy to term, may be transgenerational.
The researchers exposed pregnant mice to BPA levels equivalent to those considered safe in people from gestation day 11 until they gave birth. This exposure was associated with significant reproductive problems — including declines in fertility, sexual maturity, and pregnancy success — in three generations of female mouse offspring. The first generation of pups also experienced an abnormal estrous cycle and engaged less in typical mating behavior than mice not exposed in the womb. The third generation, which was not directly exposed to BPA either as a fetus or as an egg in a fetus in its mother's womb, experienced later sexual maturity, reduced fertility, and lower pregnancy success than mice whose ancestors were not exposed to BPA. In the third generation, the lowest dose of BPA (experienced by their great-grandmothers) interfered most with their fertility.
The researchers say that future studies should investigate the mechanism underlying the effects of BPA on female reproduction outcomes in the first to third generations of offspring.
Citation: Ziv-Gal A, Wang W, Zhou C, Flaws JA. 2015. The effects of in utero bisphenol A exposure on reproductive capacity in several generations of mice. Toxicol Appl Pharmacol 284(3):354-362.