Prenatal Exposure to Air Pollution Associated with the Fetal Growth

Researchers from CREAL, an allied ISGlobal center, have participated in a study of the Spanish INMA (Childhood and Environment) Project published in Environmental Health Perspectives. The researchers found that a Maternal exposure to NO2, associated with air pollution due the traffic in the cities, in early pregnancy was associated with reduced fetal growth based on ultrasound measures of growth during pregnancy and measures of size at birth.

“Air pollution exposure during pregnancy has been associated with impaired fetal growth. However, few studies have measured fetal biometry longitudinally, remaining unclear as to whether there are windows of special vulnerability. The aim was to investigate the impact of NO2 exposure on fetal and neonatal biometry in the Spanish INMA Project”, explained Mònica Guxens, researcher at CREAL, who has participated in this study.

Biparietal diameter (BPD), femur length (FL), abdominal circumference (AC) and estimated fetal weight (EFW) were evaluated for up to 2478 fetuses in each trimester of pregnancy. Size at 12, 20 and 34 weeks of gestation, growth between these points, as well as anthropometry at birth, were assessed by SD scores derived using cohort-specific growth curves. Temporally adjusted land-use regression was used to estimate exposure to NO2 at home addresses during the whole pregnancy period. A 10 μg/m3 increase in average exposure to NO2 during weeks 0-12 was associated with reduced growth at weeks 0-12 in AC and EFW. “The same exposure was inversely associated with reduced growth at weeks 20-34 in BPD, AC, and EFW. A less consistent pattern of association was observed for FL. The negative association of this exposure with BPD and EFW was significantly stronger in smoking versus nonsmoking mothers”, explained Guxens.

Reference

Iñiguez C. et al. Prenatal Exposure to NO2 and Ultrasound Measures of Fetal Growth in the Spanish INMA Cohort.Environ Health Perspect. 2015 Jun 26. [Epub ahead of print]

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