Prenatal exposure to particulate air pollution and gestational age at delivery in Massachusetts neonates 2001–2015

• Type of Material: Article
• Authors: Xinye Qiu, Harvard University; Kelvin C. Fong, Yale University; Liuhua Shi, Emory University; Stefania Papatheodorou, Harvard University; Qian Di, Tsinghua University; Allan Just, Icahn School of Medicine at Mount Sinai; Anna Kosheleva, Harvard University; Carmen Messerlian, Harvard University; Joel D. Schwartz, Harvard University
• Language: English
• Date: 2020-09-14
• Publisher: Lippincott, Williams & Wilkins
• Publication Version: Final Published Version
• Copyright Statement: © 2020 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of The Environmental Epidemiology. All rights reserved.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1097/EE9.0000000000000113
• Title of Journal or Parent Work: Environmental Epidemiology
• Volume: 4
• Issue: 5
• Grant/Funding Information: This study was supported by the National Institutes of Health (NIH) grant (R01 ES024332-01A1, ES-000002).; This publication was made possible also by US Environmental Protection Agency (EPA) grant (RD-835872-01).
• Keywords: Inverse probability weighting; Quantile regression; Temperature; Gestational age; Health disparity; Air pollution
• Research Categories: Environmental Sciences; Health Sciences, Public Health; Health Sciences, Obstetrics and Gynecology; Health Sciences, Epidemiology

Abstract

Background: There is a lack of evidence on causal effects of air pollution on gestational age (GA) at delivery. Methods: Inverse probability weighting (IPW) quantile regression was applied to derive causal marginal population-level GA reduction for GA percentiles associated with increased ambient particulate matter with diameter <2.5 μm (PM2.5) levels at maternal residential address for each trimester and the month preceding delivery using Massachusetts birth registry 2001 to 2015. Stratified analyses were conducted for neonatal sex, maternal age/race/education, and extreme ambient temperature conditions. Results: For neonates at 2.5th, 10th, 25th, 50th, 75th, and 97.5th percentiles of GA at delivery, we estimated an adjusted GA reduction of 4.2 days (95% confidence interval [CI] = 3.4, 5.0), 1.9 days (1.6, 2.1), 1.2 days (1.0, 1.4), 0.82 days (0.72, 0.92), 0.74 days (0.54, 0.94), and 0.54 days (0.15, 0.93) for each 5 μg/m3 increment in third trimester average PM2.5 levels. Final gestational month average exposure yielded a similar effect with greater magnitude. Male neonates and neonates of younger (younger than 35 years) and African American mothers as well as with high/low extreme temperature exposure in third trimester were more affected. Estimates were consistently higher at lower GA percentiles, indicating preterm/early-term births being more affected. Low-exposure analyses yielded similar results, restricting to areas with PM2.5 levels under US ambient annual standard of 12 μg/m3. Conclusions: Prenatal exposure to PM2.5 in late pregnancy reduced GA at delivery among Massachusetts neonates, especially among preterm/early-term births, male neonates, and neonates of younger and African American mothers. Exposure to extremely high/low temperature amplifies the effect of PM2.5 on GA.