Objectives: We aimed to examine the association between ambient residential SO2 exposure during pregnancy and missed abortion in Tianjin, an industrial city in northern China.
Methods: A population-based case-control study was conducted to investigate the relationship of maternal SO2 exposure and the risk of missed abortion. We selected 927 cases and 879 controls between 2002 and 2006 from a 15-hospital network in six districts of Tianjing. Controls were frequency matched to cases on maternal ag...