{"title":"Association between ambient air pollution a week prior to delivery and preterm birth using a nationwide study in Sweden","authors":"","doi":"10.1016/j.ijheh.2024.114443","DOIUrl":null,"url":null,"abstract":"<div><h3>Background</h3><p>Air pollution exposure has been linked with increased risk of preterm birth, which is one of the leading causes of infant mortality. Limited studies have attempted to explore these associations in low-polluted areas. In this study, we aimed to assess the association between short-term exposure to ambient air pollution and preterm birth in Sweden.</p></div><div><h3>Method</h3><p>In this population-based study we included preterm births between 2014 and 2019 from the Swedish Pregnancy Register. We applied a spatiotemporal model to estimate daily levels of particulate matter <2.5 μm (PM<sub>2.5</sub>), PM < 10 μm (PM<sub>10</sub>), nitrogen dioxide (NO<sub>2),</sub> and ozone (O<sub>3</sub>) at the residential address of each participant. We applied a time-stratified case-crossover design with conditional logistic regression analysis to estimate odds ratios (OR) of preterm birth per 10 μg/m<sup>3</sup> (PM<sub>10</sub>, NO<sub>2</sub>, O<sub>3</sub>) and 5 μg/m<sup>3</sup> (PM<sub>2.5</sub>) increase in air pollution exposure at 0–6-day lag. Two-pollutant models were applied to evaluate the independent association of each exposure on preterm birth. We also stratified by maternal characteristics to identify potential effect modifiers.</p></div><div><h3>Results</h3><p>28,216 (4.5%) preterm births were included. An increase in O<sub>3</sub> exposure was associated with increased odds of preterm birth [OR = 1.06 per 10 μg/m<sup>3</sup> (95% CI, 1.02; 1.10]. PM<sub>2.5</sub> and PM<sub>10</sub> were not significantly associated with preterm birth, and NO<sub>2</sub> displayed a negative nonlinear association with preterm birth. We did not observe any notable effect modification, but we found suggestive larger associations between O<sub>3</sub> and preterm birth when stratifying by male sex, spontaneous delivery, and spring season.</p></div><div><h3>Conclusions</h3><p>Increased O<sub>3</sub> exposure one week before delivery was associated with an increased risk of preterm birth in Sweden, a country with levels of air pollution below the current World Health Organization air quality guidelines. Increases in O<sub>3</sub> levels with climate change make these findings especially concerning.</p></div>","PeriodicalId":13994,"journal":{"name":"International journal of hygiene and environmental health","volume":null,"pages":null},"PeriodicalIF":4.5000,"publicationDate":"2024-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S143846392400124X/pdfft?md5=d1da12df51d788611e737041cfbd83ea&pid=1-s2.0-S143846392400124X-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International journal of hygiene and environmental health","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S143846392400124X","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"INFECTIOUS DISEASES","Score":null,"Total":0}
引用次数: 0
Abstract
Background
Air pollution exposure has been linked with increased risk of preterm birth, which is one of the leading causes of infant mortality. Limited studies have attempted to explore these associations in low-polluted areas. In this study, we aimed to assess the association between short-term exposure to ambient air pollution and preterm birth in Sweden.
Method
In this population-based study we included preterm births between 2014 and 2019 from the Swedish Pregnancy Register. We applied a spatiotemporal model to estimate daily levels of particulate matter <2.5 μm (PM2.5), PM < 10 μm (PM10), nitrogen dioxide (NO2), and ozone (O3) at the residential address of each participant. We applied a time-stratified case-crossover design with conditional logistic regression analysis to estimate odds ratios (OR) of preterm birth per 10 μg/m3 (PM10, NO2, O3) and 5 μg/m3 (PM2.5) increase in air pollution exposure at 0–6-day lag. Two-pollutant models were applied to evaluate the independent association of each exposure on preterm birth. We also stratified by maternal characteristics to identify potential effect modifiers.
Results
28,216 (4.5%) preterm births were included. An increase in O3 exposure was associated with increased odds of preterm birth [OR = 1.06 per 10 μg/m3 (95% CI, 1.02; 1.10]. PM2.5 and PM10 were not significantly associated with preterm birth, and NO2 displayed a negative nonlinear association with preterm birth. We did not observe any notable effect modification, but we found suggestive larger associations between O3 and preterm birth when stratifying by male sex, spontaneous delivery, and spring season.
Conclusions
Increased O3 exposure one week before delivery was associated with an increased risk of preterm birth in Sweden, a country with levels of air pollution below the current World Health Organization air quality guidelines. Increases in O3 levels with climate change make these findings especially concerning.
期刊介绍:
The International Journal of Hygiene and Environmental Health serves as a multidisciplinary forum for original reports on exposure assessment and the reactions to and consequences of human exposure to the biological, chemical, and physical environment. Research reports, short communications, reviews, scientific comments, technical notes, and editorials will be peer-reviewed before acceptance for publication. Priority will be given to articles on epidemiological aspects of environmental toxicology, health risk assessments, susceptible (sub) populations, sanitation and clean water, human biomonitoring, environmental medicine, and public health aspects of exposure-related outcomes.