Gestational and postnatal exposures to fine particulate matter (PM) and their association with acute ear infections, diarrhea, respiratory symptoms, and mortality: A longitudinal study of infants in the multicountry Household Air Pollution Intervention Network (HAPIN) trial.

Exposure to household air pollution from cooking with biomass is a risk factor for infant morbidity and mortality. The Household Air Pollution Intervention Network (HAPIN) evaluated the effects of a liquefied petroleum gas (LPG) stove and fuel intervention on air pollutant exposure and health outcomes among 3195 pregnant women (nine to 19 weeks' gestation) and their infants in Guatemala, India, Peru, and Rwanda. We measured PM exposure among women before childbirth and infants in the postnatal period. Infant death was monitored for the entirety of the study, while data on acute ear infections, diarrhea, cough, and rapid and/or difficulty breathing were collected at four timepoints. Multivariable logistic regression models, adjusted for demographics and repeated measures within each child, estimated the odds of each health outcome based on exposures. We observed a modest but statistically significant association between an interquartile increase in gestational PM exposure and increased odds of acute ear infection (OR: 1.15; 95 % CI: 1.00, 1.33), but there was no association with other measured health outcomes. We found no statistically significant association between postnatal PM exposure and any of the measured health outcomes. Our findings underscore the need for further investigation into the environmental determinants of infant health.