Association between maternal exposure to particulate matter (PM2.5) and adverse pregnancy outcomes in Lima, Peru

<jats:title>Abstract</jats:title><jats:p>The literature shows associations between maternal exposures to PM<jats:sub>2.5</jats:sub> and adverse pregnancy outcomes. There are few data from Latin America. We have examined PM<jats:sub>2.5</jats:sub> and pregnancy outcomes in Lima. The study included 123,034 births from 2012 to 2016, at three public hospitals. We used estimated daily PM<jats:sub>2.5</jats:sub> from a newly created model developed using ground measurements, satellite data, and a chemical transport model. Exposure was assigned based on district of residence (<jats:italic>n</jats:italic> = 39). Linear and logistic regression analyzes were used to estimate the associations between air pollution exposure and pregnancy outcomes. Increased exposure to PM<jats:sub>2.5</jats:sub> during the entire pregnancy and in the first trimester was inversely associated with birth weight. We found a decrease of 8.13 g (−14.0; −1.84) overall and 18.6 g (−24.4, −12.8) in the first trimester, for an interquartile range (IQR) increase (9.2 µg/m<jats:sup>3</jats:sup>) in PM<jats:sub>2.5</jats:sub>. PM<jats:sub>2.5</jats:sub> exposure was positively associated with low birth weight at term (TLBW) during entire pregnancy (OR: 1.11; 95% CI: 1.03–1.20), and at the first (OR: 1.11; 95% CI: 1.03–1.20), second (OR: 1.09; 95% CI: 1.01–1.17), and third trimester (OR: 1.10; 95% CI: 1.02–1.18) per IQR (9.2 µg/m<jats:sup>3</jats:sup>) increase. Higher exposure to PM<jats:sub>2.5</jats:sub> was also associated with increased risk of small for gestational age (SGA). There were no statistically significant associations between PM<jats:sub>2.5</jats:sub> exposure and preterm births (PTB). Exposure to higher concentrations of PM<jats:sub>2.5</jats:sub> in Lima may decrease birth weight and increase the frequency of TLBW and SGA. Our study was inconsistent with the literature in finding no associations with preterm birth.</jats:p>