Maternal Exposure to Particulate Air Pollution and Term Birth Weight: A Multi-Country Evaluation of Effect and Heterogeneity

• Type of Material: Article
• Authors: Payam Dadvand, Centre for Research in Environmental Epidemiology (CREAL); Jennifer Parker, Centers for Disease Control and Prevention; Michelle L. Bell, Yale University; Matteo Bonzini, University of Insubria; Michael Brauer, University of British Columbia; Lyndsey Darrow, Emory University; Ulrike Gehring, University of Utrecht; Svetlana V. Glinianaia, Newcastle University; Nelson Gouveia, University of São Paulo; Eun-hee Ha Ha, Ewha Womans University; Jong Han Leem, Inha University; Edith H. van den Hooven, Erasmus Medical Center; Bin Jalaludin, Evidence Management and Surveillance; Bill M. Jesdale, University of California Berkeley; Johanna Lepeule, Harvard University; Rachel Morello-Frosch, University of California Berkeley; Geoffrey G. Morgan, North Coast Area Health Service; Angela Cecilia Pesatori, University of Milan; Frank H. Pierik, Urban Environment and Safety, TNO; Tanja Pless-Mulloli, Newcastle University; David Q. Rich, University of Rochester; Sheela Sathyanarayana, University of Washington; Juhee Seo, Ewha Womans University; Rémy Slama, INSERM; Matthew Strickland, Emory University; Lillian Tamburic, University of British Columbia; Daniel Wartenberg, University of Medicine & Dentistry New Jersey; Mark J. Nieuwenhuijsen, Centre for Research in Environmental Epidemiology (CREAL); Tracey J. Woodruff, University of California San Francisco
• Language: English
• Date: 2013-03-01
• Publisher: National Institute of Environmental Health Sciences (NIEHS)
• Publication Version: Final Published Version
• Copyright Statement: Publication of EHP lies in the public domain and is therefore without copyright. All text from EHP may be reprinted freely. Use of materials published in EHP should be acknowledged (for example, ?Reproduced with permission from Environmental Health Perspectives?); pertinent reference information should be provided for the article from which the material was reproduced. Articles from EHP, especially the News section, may contain photographs or illustrations copyrighted by other commercial organizations or individuals that may not be used without obtaining prior approval from the holder of the copyright.
• Final Published Version (URL): http://dx.doi.org/10.1289/ehp.1205575
• Title of Journal or Parent Work: Environmental Health Perspectives
• ISSN: 0091-6765
• Volume: 121
• Issue: 3
• Start Page: 367
• End Page: 373
• Grant/Funding Information: This project was supported by the U.S. Environmental Protection Agency under contract number EP-W-05-022 and by the National Institute of Environmental Health Sciences (R01ES016317, R01ES019587).; For the Vancouver analysis, the British Columbia (BC) Ministry of Health, the BC Vital Statistics Agency, and the BC Reproductive Care Program approved access to and use of the data facilitated by Population Data BC.; The U.K. PAMPER study was supported by the Wellcome Trust (grant 072465/Z/03/Z). P.D. is funded by a Juan de la Cierva fellowship (JCI-2011-09937) awarded by the Spanish Ministry of Science and Innovation.
• Keywords: heterogeneity; air pollution; INFANTS; RISK; PREGNANCY OUTCOMES; Life Sciences & Biomedicine; HEALTH; fetal growth; ICAPPO; particulate matter; low birth weight; PUBLIC, ENVIRONMENTAL & OCCUPATIONAL HEALTH, SCI; meta-regression; Toxicology; ENVIRONMENTAL SCIENCES; Environmental Sciences; Public, Environmental & Occupational Health; Environmental Sciences & Ecology; Science & Technology; pregnancy; multi-center study; meta-analysis; METAANALYSIS
• Research Categories: Health Sciences, Epidemiology; Health Sciences, Public Health

Abstract

Background: A growing body of evidence has associated maternal exposure to air pollution with adverse effects on fetal growth; however, the existing literature is inconsistent. Objectives: We aimed to quantify the association between maternal exposure to particulate air pollution and term birth weight and low birth weight (LBW) across 14 centers from 9 countries, and to explore the influence of site characteristics and exposure assessment methods on between-center heterogeneity in this association. Methods: Using a common analytical protocol, International Collaboration on Air Pollution and Pregnancy Outcomes (ICAPPO) centers generated effect estimates for term LBW and continuous birth weight associated with PM10 and PM2.5 (particulate matter ≤ 10 and 2.5 μm). We used meta-analysis to combine the estimates of effect across centers (~ 3 million births) and used meta-regression to evaluate the influence of center characteristics and exposure assessment methods on between-center heterogeneity in reported effect estimates. Results: In random-effects meta-analyses, term LBW was positively associated with a 10-μg/m3 increase in PM10 [odds ratio (OR) = 1.03; 95% CI: 1.01, 1.05] and PM2.5 (OR = 1.10; 95% CI: 1.03, 1.18) exposure during the entire pregnancy, adjusted for maternal socioeconomic status. A 10-μg/m3 increase in PM10 exposure was also negatively associated with term birth weight as a continuous outcome in the fully adjusted random-effects meta-analyses (-8.9 g; 95% CI: -13.2, -4.6 g). Meta-regressions revealed that centers with higher median PM2.5 levels and PM2.5:PM10 ratios, and centers that used a temporal exposure assessment (compared with spatiotemporal), tended to report stronger associations. Conclusion: Maternal exposure to particulate pollution was associated with LBW at term across study populations. We detected three site characteristics and aspects of exposure assessment methodology that appeared to contribute to the variation in associations reported by centers.