IRP study suggests higher air pollution exposure during second pregnancy may increase preterm birth risk

Thursday, September 12, 2019

Pregnant women who are exposed to higher air pollution levels during their second pregnancy, compared to their first one, may be at greater risk of preterm birth, according to researchers at the National Institutes of Health. Their study appears in the International Journal of Environmental Research and Public Health.

Preterm birth, or the birth of a baby before 37 weeks, is one of the leading causes of infant mortality in the United States, according to the Centers for Disease Control and Prevention. Although previous studies have found an association between air pollution exposure and preterm birth risk, the authors believe their study is the first to link this risk to changes in exposure levels between a first and second pregnancy.

“What surprised us was that among low-risk women, including women who had not delivered preterm before, the risk during the second pregnancy increased significantly when air pollution stayed high or increased,” said Pauline Mendola, Ph.D., the study’s lead author and a senior investigator in the Epidemiology Branch at the Eunice Kennedy Shriver National Institute of Child Health and Human Development.