Air pollutant exposure and preterm and term small-for-gestational-age births in Detroit, Michigan: Long-term trends and associations

► The association between ambient air pollutants and adverse birth outcomes was examined. ► Term small-for-gestational-age (SGA) and preterm birth (PTB) were the main health outcomes. ► Long-term trends in air pollutant levels, and maternal smoking and race were accounted for. ► The early period of pregnancy is important for CO-SGA, NO2-SGA and O3-PTB associations. ► The late pregnancy period is important for O3-SGA (summer), PM10-SGA and SO2-PTB associations.