(HealthDay News) – Exposure to ambient air pollution is associated with low birth weight at term, according to a study published online Oct. 15 in The Lancet Respiratory Medicine.
Marie Pederson, PhD, from the Centre for Research in Environmental Epidemiology in Barcelona, Spain, and colleagues pooled data from 14 population-based mother-child cohort studies to examine the effect of maternal exposure to low concentrations of ambient air pollution on birth weight. The study population included 74,178 women with singleton deliveries.
The researchers found that the risk of low birth weight at term was increased with a 5µg/m³ increase in the concentration of particulate matter with an aerodynamic diameter of <2.5µm (PM2.5) (adjusted odds ratio, 1.18). An increased risk was also seen at pregnancy concentration lower than the European Union PM2.5 limit (5µg/m³ increase in concentration of PM2.5 for those with exposure to <20µg/m³: odds ratio, 1.41). The risk of low birth weight was also increased with PM10, nitrogen dioxide, and traffic density on nearest street. A reduction in the PM2.5 concentration to 10µg/m³ during pregnancy would correspond to a 22% decrease in low birth weight at term.
“Exposure to ambient air pollution in pregnancy at levels currently reported in Europe is associated with reduced fetal growth,” the authors write.