Association of Low Birthweight and Indoor Air Pollution: Biomass Fuel Use in Bangladesh

Abstract

Background. More than 90% of all low birthweight (LBW) babies are born in developing countries, and half of the population in developing nations uses solid fuels as their primary source of energy for cooking. An association between household use of solid biomass fuels and reduced newborn weight has been found in a number of countries. Bangladesh has a high prevalence of LBW babies (22%), and 88% of the population use solid fuels for cooking. Objectives. This study aims to explore whether indoor air pollution is associated with LBW in Bangladesh, an important determinant of infant mortality and morbidity. Methods. The 2011 Bangladesh Demographic and Health Survey (BDHS) was used for the present analysis. The total number of births reported in the previous five years by respondents in the survey sample was 8,753. Mothers' recall of their baby's weight was the dependent dichotomous variable. A mixed effects logistic regression model was fitted using region as a random effect and several independent fixed effects. Results. High pollutant cooking fuels, such as coal and wood, resulted in higher odds of having a LBW child compared to use of electricity/gas (odds ratio (OR): 2.6, confidence interval (CI): 1.1–6.2 and OR: 1.1, CI: 1.0–1.2). Factors which lowered the odds include mothers with a bachelor's degree or higher education (OR: 0.6, CI: 0.4–0.9), third order children (OR: 0.8, CI: 0.6–0.9), fourth or higher order children (OR: 0.8, CI: 0.6–1.0), having a male child (OR: 0.7, CI: 0.7–0.8), and receiving sufficient antenatal care (OR: 0.8, CI: 0.6–0.9). Factors which increase the odds of having a LBW infant include mothers who are underweight compared to normal weight mothers (OR: 1.1, CI: 1.1–1.2), mistimed pregnancies (OR: 1.2, CI: 1.0–1.4), or unplanned pregnancies (OR: 1.3, CI: 1.0–1.7), compared to planned pregnancies. Conclusions. This is the first paper to show an association between use of highly pollutant biomass fuel and prevalence of LBW babies in Bangladesh, suggesting that besides polluting the air and causing respiratory illnesses, biomass fuel combustion may also affect the health of fetuses in utero. Further longitudinal studies are required to establish this finding among mothers in developing countries.