Human Environments Analysis Lab (HEAL)

Title

Geospatial analyses of adverse birth outcomes in Southwestern Ontario: Examining the impact of environmental factors

Document Type

Article

Publication Date

5-2019

Journal

Environmental Research

Volume

172

First Page

18

Last Page

26

URL with Digital Object Identifier

https://doi.org/10.1016/j.envres.2018.12.068

Abstract

Background

A growing body of research has examined the association between exposure to environmental factors during pregnancy and adverse birth outcomes; however, many studies do not control for potential covariates and findings vary considerably.

Objective

To test the relative influence of environmental factors including exposure to air pollution, major roads, highways, industry, parks, greenspaces, and food retailers on low birth weight (LBW) and preterm birth (PTB) in Southwestern Ontario (SWO), Canada, while accounting for medical (e.g., previous preterm birth, gestational diabetes), behavioral (e.g., alcohol, smoking), demographic (e.g., maternal age, body mass index), and neighborhood-level socioeconomic (e.g., household income, education) factors.

Methods

This retrospective cohort study consisted of a large sample of pregnant women from SWO who gave birth to singleton newborns between February 2009 and February 2014 at London Health Sciences Centre. Data on maternal postal codes were entered into a Geographic Information System to map the distribution of maternal residences and determine selected characteristics of their neighborhood environments (i.e., socioeconomic, built, natural). These variables were developed based on postal codes where the mothers lived prior to giving birth. Logistic regression was used to assess the relative effects of the physical environment, socioeconomic status, clinical history, and behavioral risk factors on mothers having a LBW or PTB infant.

Results

Out of 25,263 live births, 5.7% were LBW and 7.5% were PTB. Exposure to sulfur dioxide was a top predictor of both LBW and PTB. For every one-unit increase in sulfur dioxide, the odds of a LBW and PTB were 3.4 (95% CI: 2.2, 5.2) and 2.0 (95% CI: 1.4, 3.0) times higher, after controlling for other variables in the model, respectively (p < 0.001). Previous PTB was also highly associated with both birth outcomes.

Conclusions

Health care providers should be informed about the hazards of air pollution to developing fetuses so that recommendations can be made to their pregnant patients about limiting exposure when air quality is poor.

Find in your library

Share

COinS