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Measuring Carbon Content in Airway Macrophages Exposed to Carbon-Containing Particulate Matters
Published on: July 12, 2024
A global systematic review and meta-analysis on preterm birth and air pollution exposure
Majid Kermani1, Homa Kashani2, Pegah Nakhjirgan3
1Research Center for Environmental Health Technology, Iran University of Medical Sciences, Tehran, Iran; Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, Tehran, Iran.
Objective:
Evidence on the association between ambient air pollutants and preterm birth (PTB) is increasing, yet findings remain inconsistent. This study aims to systematically review and synthesize evidence on the association between maternal exposure to ambient pollutants (PM2.5, PM10, NO2, SO2, and O3) and the risk of PTB.
Study Design:
A systematic review and meta-analysis.
Methods:
A comprehensive search of PubMed, Web of Science, and Scopus (2014-2024) identified 69 eligible studies. Of these, 66 studies (n = 66) were included in the meta-analysis. Using random-effects models, the study evaluated the impact of air pollutants on PTB risk.
Results:
Based on cohort studies, which provide the highest level of evidence, an increase of 1 μg/m3 in air pollutants (PM2.5, PM10, NO2, and O3) was significantly associated with an increased risk of PTB. The results are presented as follows: (PM2.5: pooled RR = 1.016, 95% CI: 1.010-1.021, PM10: (pooled RR = 1.004, 95% CI: 1.002-1.007), NO2 (pooled RR = 1.007, 95% CI: 1.00-1.013), O3 (pooled RR = 1.004, 95% CI: 1.001-1.006). Additionally, this study examined the association between air pollutants and PTB across the three trimesters of pregnancy. Based on cohort studies, a significant association was observed between NO2 and particulate matter exposure during the third trimester and PTB.
Conclusion:
Although the number of observational studies in this field is limited and further research is needed, current evidence suggests that air pollutants, particularly particulate matter, may increase the risk of PTB. Therefore, effective health policies are essential to mitigate these harmful effects.
