中文摘要：

目的探讨怀孕早、中、晚期以及妊娠全程氯化消毒副产物（CDBPs）暴露对足月儿出生体重的影响。方法以某水厂管网末梢水中CDBPs的监测数据为评价外暴露的重要指标，选择妊娠期间一直居住在该厂供水范围的孕妇为研究对象，采用回顾性研究方法分析妊娠不同时期三氯甲烷和溴代三卤甲烷（一溴二氯甲烷、二溴一氯甲烷和三溴甲烷之和）以及二氯乙酸和三氯乙酸暴露量与足月儿出生体重的关系。结果将CDBPs暴露水平按四分位数分组后发现，孕晚期三氯甲烷与溴代三卤甲烷高暴露（P76-P100）可能会引起足月儿出生体重的降低，OR值分别为1．82和1．51，95％C1分别为1．10～3．02和1．05—2．17。孕早期中浓度三氯甲烷暴露（P26-P50）也可能与出生体重降低有关（OR=1．74，95％C1为1．10．2．77）。在孕早期联合中期的高浓度二氯乙酸暴露（P76-P100）和中浓度三氯甲烷暴露（P51-P75）可能与足月儿出生体重降低有关，OR值分别为1．60和1．62，95％C1分别为1．02—2．47和1．05～2．50。结论妊娠期间暴露CDBPs可能引起足月儿出生体重降低，此结果需要在更大人群样本中加以验证。

英文摘要：

Objective To study the effects of trimester-specific and pregnancy average exposure to chlorinated disinfection by-products （CDBPs） in drinking water on term infants birth weight. Methods The concentration of disinfection by-products in a certain water supply system was monitored monthly and was used as a main index for exposure estimation. The selected subjects were with singleton birth and their water supply was from this single water plant during the whole pregnancy. Retrospective method was utilized in this study to assess the effects of CDBPs on term infants birth weight. Results The risk of low birth weight was elevated when comparing increasing quartiles of exposure to constituents of CDBPs. We found high exposure （P76-P100）to chloroform and hromo-trihalomethanes during the last trimester could result in decreased birth weight （OR = 1.82,95% CI： 1.10- 3.02; OR = 1.51,95 % CI： 1.05 -2.17, respectively）.Besides, moderate-expose （ P26-Pso ） to chloroform during first trimester may be related to decreased birth weight. When combined the exposure of the first trimester and second trimester,we also found exposure to high levels （P76-P100） of dichloroacetie acid and moderate levels （P51-P75） of bichloraeetic acid could affect term infants birth weight （OR=1.60,95%CI=1.02-2.47;OR=1.62,95%CI=1.05-2.50,respectively）. Conclusion Exposure to CDBPs during pregnancy may affect term infants birth weight. However,these results need to be confirmed in large scale studies.