Effects of exposure to indoor air pollution due to biomass fuel combustion on birth outcomes: a prospective birth cohort study

Abstract

Introduction. Indoor air pollution is considered a major public health problem. The aim of this study was to evaluate thr relationship between exposure to indoor air pollution due to combustion of biomass fuels and pregnancy outcomes. Methods. We assembled a cohort of 721 women in their first trimester of pregnancy attending antenatal clinics at the Colombo North Teaching Hospital at Ragama, Sri Lanka; we classified 386 women using biomass fuel or kerosene as the high exposure group, and 335 women using liquefied petroleum gas or electricity as the low exposure group based on the principal cooking fuel in the first trimester of pregnancy.. Women were followed up until delivery, and birth weight, birth length and occipitofrontal circumference and Apgar scores were measured at birth. Results. Among the high exposure group, there were 16 abortions and 2 twin deliveries; 12 abortions, 3 twin deliveries and one still birth occurred among the the low exposure group.. Of 538 babies whose gestational age was known and who were assessed at birth, 30 out of 296 (10.5%) babies in the high exposure group and 29 out of 242 (12.0%) babies in the low exposure group were preterm (<37 weeks) (p=0.58). There were significant differences between term babies (period of amenorrhea > 37 weeks) born to mothers in high and low exposure groups in birth weight (2.90 Kg vs. 3.03 Kg ; p=0.004), birth length (49.89 cm vs. 50.57 cm; p=0.031) and occipitofrontal circumference (33.37 cm vs. 33.76 cm ; p=0.037). Differences in Apgar scores at 1 min, 5 min and 10 min between babies born to women in the high and low exposure were unremarkable.Conclusions There was evidence that exposure to indoor air pollution due to combustion of biomass fuels in pregnancy has adverse effects on birth weight, birth length and occipitofrontal circumference of term babies but not on the Apgar scores, in this group of women. Conclusions. There was evidence that exposure to indoor air pollution due to combustion of biomass fuels in pregnancy has adverse effects on birth weight, birth length and occipitofrontal circumference of term babies but not on the Apgar scores, in this group of women.