Prenatal air pollution exposure tied to increased cerebral palsy risk

Prenatal exposure to fine particulate matter appears to put newborns at risk of cerebral palsy, as shown in a study.

For the population-based cohort study, researchers used province-wide health administrative databases in Ontario, Canada, and identified 1,587,935 mother-child pairs who reached term gestation.

Satellite-based estimates and ground-level monitoring data were used to evaluate weekly average concentrations of ambient fine particulate matter with a diameter of 2.5 μm (PM2.5) or smaller, nitrogen dioxide (NO2), and ozone (O3) during pregnancy. Meanwhile, cerebral palsy was ascertained by a single inpatient hospitalization diagnosis or at least two outpatient diagnoses for children from birth to age 18 years.

The mean maternal age was 30.1 years, and 811,745 infants were male (51.1 percent). Cerebral palsy was diagnosed in 3,170 children (0.2 percent). Each 2.7-μg/m³ increase in prenatal ambient PM2.5 concentration was associated with a 12-percent higher cumulative risk of cerebral palsy (cumulative hazard ratio [CHR], 1.12, 95 percent confidence interval [CI], 1.03–1.21).

Notably, the CHR of cerebral palsy was higher in male infants than in female infants (1.14, 95 percent CI, 1.02–1.26 vs 1.08, 95 percent CI, 0.96–1.22).

PM2.5 exposure seemed to be a constant hazard throughout pregnancy for cerebral palsy risk, with no specific window of susceptibility observed.

Prenatal NO2 or O3 exposure showed no associations with cerebral palsy risk.

More studies are needed to validate the findings and explore potential biological pathways linking PM2.5 exposure to cerebral palsy in offspring.