Ambient air pollution and adverse birth outcomes: a natural experiment study

Authors

Cheng Huang, George Washington University
Catherine Nichols, George Washington University
Yang Liu
Yunping Zhang
Xiaohong Liu
Suhong Gao
Zhiwen Li
Aiguo Ren

Document Type

Journal Article

Publication Date

7-2015

Journal

Population Health Metrics

Volume

13

Inclusive Pages

17

DOI

10.1186/s12963-015-0050-4

Abstract

Background

Radical regulations to improve air quality, including traffic control, were implemented prior to and during the 2008 Beijing Olympic Games. Consequently, ambient concentrations of nitrogen dioxide (NO ₂ ) and particular matter 10 micrometers or less (PM ₁₀ ), were reduced in a distinct and short window of time, which presented a natural experiment for testing the relationships between maternal exposure to PM ₁₀ and NO ₂ during pregnancy and adverse birth outcomes.

Methods

We estimated the effect of PM ₁₀ and NO ₂ exposure during each trimester of gestation on the risk of preterm birth among live births and the birth weight among term babies. The data were based on 50,874 live births delivered between January 1, 2006 and December 31, 2010 at the Beijing Haidian Maternal and Child Health Hospital. Air monitoring data for the same period were obtained from the Beijing Municipal Environmental Monitoring Center.

Results

Among full-term births, maternal exposure to NO ₂ in the third trimester predicted birth weight, with each 10-unit increment (per 10 ug/m ³ ) in NO ₂ concentration associated with a 13.78 g (95 % confidence interval: −21.12, −6.43; p < 0.0001) reduction in birth weight. This association was maintained after adjusting for other pollutants, including carbon monoxide (CO), sulfur dioxide (SO ₂ ), and PM ₁₀ . No relationship was found between the concentration of PM ₁₀ and low birth weight among full-term births. Neither PM ₁₀ nor NO ₂ concentrations predicted the risk of premature birth.

Conclusions

Exposure to ambient air pollution during certain periods of pregnancy may decrease birth weight, but the effect size is small.

Comments

Reproduced with permission of BioMed Central. Population Health Metrics.

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 License.

APA Citation

Huang, C., Nichols, C., Liu, Y., Zhang, Y., Liu, X. et al. (2015). Ambient air pollution and adverse birth outcomes: a natural experiment study. Population Health Metrics, 13:17.

Peer Reviewed

1

Open Access

1