A study examining increased preterm birth rates in the United States has found “little evidence of a relationship been BPA [bisphenol A] and prematurity.” David Cantonwine, et al., “Urinary Bisphenol A Levels during Pregnancy and Risk of Preterm Birth,” Environmental Health Perspectives, September 2015. After analyzing urinary BPA levels throughout pregnancy in 130 cases of preterm birth (PTB) and 352 randomly assigned controls, researchers with Harvard Medical School and University of Michigan School of Public Health report that,“[i]n adjusted models, urinary BPA averaged across pregnancy was not significantly associated with PTB.” They note, however, that “averaged BPA exposure during pregnancy was associated with significantly increased odds of being delivered preterm among females, but not males.”

“Our study had several strengths, including a repeated time point assessment of BPA exposure, ultrasound dating of gestational age, physician-validated clinical outcomes, and a large number of subjects and preterm cases, which allowed for exploring the heterogeneous nature of PTB,” concludes the study. “Still, results from our secondary analyses of subtypes of PTB and stratification on infant sex should be interpreted cautiously… We acknowledge that the few significant associations found in our analysis may be attributable to chance alone, and larger follow-up studies to replicate the findings are warranted.”