Abstract:
Effect of indoor air pollution (IAP) on birth weight remains largely unexplored but yet
purported as the most important environmental exposure for pregnant women in developing
countries due to the effects of second-hand smoke. We investigated the associations between
the determinants of indoor air quality in households and birth weight. Methods
A cross-sectional study of 592 mothers and their newborns using postnatal services at the
Korle Bu Teaching Hospital located in Accra, Ghana was conducted in 2010 to collect
information on characteristics of indoor environment and other potential determinants of fetal
growth. Birth weight was recorded from hospital records.
Results
Household cooking fuel choices and garbage burning practices were determinants of birth
weight. Multivariate linear regression analysis adjusting for age, social class, marital status
and gravidity of mothers, and sex of neonate resulted in a 243g (95% CI: 496, 11) and 178g
(95% CI: 421, 65) reduction in birth weight for use of charcoal, and garbage burning
respectively compared with use of LPG only. The estimated reductions in birth weight was
not statistically significant. Applying the ordinal scale exposure parameter nonetheless
revealed a significant exposure-response relationship between maternal exposures from
charcoal use and garbage burning, and birth weight. Generalized linear models adjusting for
confounders resulted in a 41% (risk ratio [RR] = 1.41; 95% CI: 0.62, 3.23) and 195%
(RR=2.95; 95% CI: 1.10, 7.92) increase in the risk of low birth weight (LBW) for use of
charcoal, and garbage burning respectively compared with use of LPG only. A combination
of charcoal use and household garbage burning during pregnancy on fetal growth resulted in
a 429g (95% CI: 259, 599) reduction in birth weight and 316% (RR=4.16; 95% CI: 2.02,
8.59) excess risk of LBW. Sensitivity analysis performed by restricting the analysis to term
births produced similar results.
Conclusions
Maternal use of charcoal as a cooking fuel during pregnancy and burning of garbage at home
are strong determinants of average fetal growth and risk of LBW. Efforts to reduce maternal
exposures to IAP are thus important to improve birth outcomes.
