[Maternal sulfur dioxide exposure and the risk of low birth-weight babies].

The relationship between maternal exposure to sulfur dioxide (SO2) and the risk of low birth-weight (LBW) babies which has been reported in literatures remained inconclusive. In this study, the data on SO2 emission, meteorology, topography as well as LBW and control babies in the Dallas-Fort Worth area of the United States in 1997 were collected to re-examine the associations between maternal SO2 exposure and the risk of LBW in babies. A combination of air dispersion modeling, Geographic Information System (GIS) spatial interpolation and geo-statistical analysis, as well as logistic regression was used for analyses. Results showed that the risk of LBW was not significantly increased with the exposure of pregnant mothers to higher level of SO2 when all data were considered together as one group. However, for mothers at the age 35 or older, the risk of LBW babies was higher in exposure to SO2 (OR = 2.31, 95% CI 1.01 - 5.30). Therefore, the potential risk of LBW baby might be higher in elder women in exposure to SO2 during pregnancy.