Outdoor Air Pollution, Preterm Birth, and Low Birth Weight: Analysis of the World Health Organization Global Survey on Maternal and Perinatal Health

http://dx.doi.org/10.1289/ehp.1306837



Table 2. Adjusted ORs (95% CI) for preterm birth and LBW associated with a 10-μg/m3 increase in PM2.5 and with quartiles of PM2.5 (relative to the lowest quartile) after adjusting exposure estimates to account for seasonality, WHO Global Survey on Maternal and Perinatal Health, 2004–2008.
Outcome Model 1 Model 2
All models are GEE models with a logit link. All models were adjusted for mother’s age, education, parity, prenatal care, and infant’s sex. Model 2 also adjusted for country-level variables GDP per capita, urbanicity, health care expenditure per capita, and Gini coefficient. Models for 10 μg/m3 PM2.5 and quartiles of PM2.5 were run separately. PM2.5 levels were seasonally adjusted.
Preterm birth    
PM2.5 (10 μg/m3) 0.96 (0.91, 1.02) 0. 96 (0.90, 1.02)
< 6.35 1.0 (Reference) 1.0 (Reference)
6.35 to < 12.32 1.08 (0.95, 1.22) 1.08 (0.95, 1.24)
12.32 to < 22.20 1.05 (0.90, 1.23) 1.06 (0.90, 1.25)
≥ 22.20 0.96 (0.79, 1.17) 0.96 (0.79, 1.18)
LBW    
PM2.5 (10 μg/m3) 1.00 (0.97, 1.03) 0.99 (0.96, 1.01)
< 6.298 1.0 (Reference) 1.0 (Reference)
6.298 to <11.96 1.06 (0.97, 1.16) 1.05 (0.95, 1.16)
11.96 to <20.16 1.19 (1.06, 1.33) 1.15 (1.02, 1.30)
≥ 20.16 1.22 (1.07, 1.39) 1.15 (1.01, 1.32)