Maternal Exposure to Air Pollution Is Associated with Neonatal Jaundice: A Retrospective Cohort Study

Objective To evaluate the association between maternal ambient pollutant exposure and neonatal jaundice in multiple pollutant species and examine sex differences. Study design Epidemiologic study: Records of 13 297 newborns (6153 male, 7144 female) born in Taichung, Taiwan were obtained from a national database. Average concentrations of prenatal air pollutants 3 months prior to birth were divided into low, middle, and high levels. Neonatal jaundice phototherapy rates between mothers who suffered varying air pollutant levels were compared. Clinical study: Three hundred seventy-six newborns (189 male, 187 female) born and received jaundice treatment with phototherapy in a hospital in Taichung, Taiwan were recruited. The correlation between prenatal exposure to air pollutants 3 months prior to birth, newborn's serum bilirubin, and serum hemoglobin were calculated. Results Epidemiologic study: Male newborns born to mothers exposed to high carbon monoxide (CO), nitric oxide (NO), nitrogen dioxide (NO2), and methane (CH4) levels had higher phototherapy rates. In female newborns, the same was noted for CO and CH4. Clinical study: Male newborns had a positive correlation between CO, <= 2.5 mu m diameter particles, <= 10 mu m diameter particles, NO, NO2, nonmethane hydrocarbon, and CH4 exposure 3 months prior to birth and serum bilirubin levels. Female newborns had a positive correlation for CH4. A positive correlation between CO, <= 2.5 mu m diameter particles, <= 10 mu m diameter particles, NO2, nonmethane hydrocarbon, CH4 expo- sure, and serum hemoglobin levels was noted in male newborns. Conclusion Maternal exposure to air pollutants may increase neonatal jaundice treatment rates for phototherapy and higher neonatal serum total bilirubin level. Higher hemoglobin levels because of higher pollutant exposures may explain our findings. The association was more obvious in male newborns.