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 3. Adjusted ORs (95% CI) for preterm birth and LBW associated with 10-μg/m3 PM2.5 and with quartiles of PM2.5 (relative to the lowest quartile) after adjusting exposure estimates to account for seasonality for China and India, WHO Global Survey on Maternal and Perinatal Health, 2004–2008.
Exposure Preterm birth LBW
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. Models for 10 μg/m3 PM2.5 and ­quartiles of PM2.5 were run separately. PM2.5 levels were seasonally adjusted.
China    
PM2.5 (10 μg/m3) 1.11 (1.04, 1.17) 1.07 (1.01, 1.14)
< 12.5 1.0 (Reference) 1.0 (Reference)
12.5 to < 17.7 0.77 (0.45, 1.13) 0.98 (0.70, 1.39)
17.7 to < 36.5 0.97 (0.70, 1.34) 1.08 (0.84, 1.40)
≥ 36.5 2.54 (1.42, 4.55) 1.99 (1.06, 3.72)
India    
PM2.5 (10 μg/m3) 0.96 (0.91, 1.03) 0.97 (0.95, 0.99)
< 18.8 1.0 (Reference) 1.0 (Reference)
18.8 to < 35.3 1.08 (0.87, 1.34) 1.01 (0.96, 1.07)
35.3 to < 70.3 0.92 (0.72, 1.19) 0.90 (0.79, 1.02)
≥ 70.3 0.76 (0.49, 1.17) 0.82 (0.75, 0.90)