目的　了解目前北京城区孕妇血铅水平、脐带血铅水平及产妇乳汁铅水平 ,探讨三者之间的关系 ,并分析孕妇铅暴露的影响因素。　方法　将孕妇按不同孕周分为早孕、中孕和晚孕三组 ,收集孕妇静脉血 ,于胎儿娩出时收集脐带血 ,于产后 3d收集产妇乳汁。所有样本采用石墨炉原子吸收法进行铅含量的测定。采用自行编制的问卷对调查对象进行有关环境、生活方式、膳食情况的调查以分析孕妇铅暴露的影响因素。　结果　共收集孕产妇静脉血 115 1例 ,孕期血铅中位数为 4 3.4 0μg/L。孕期血铅呈动态变化 ,孕中期最低为 37.4 0 μg/L ,孕早、晚期较高 ,分别为 4 4 .5 0 μg/L和4 5 .10μg/L ,差异有显著性 ,P <0 .0 0 1。文化程度、家用燃料、乳制品摄入量这三个因素对血铅的影响具有统计学意义。收集脐带血 4 34例 ,铅中位数为 2 6 .4 0 μg/L ,与母体血铅呈正相关 ,r =0 .36 5 ,P <0 .0 0 1。收集乳汁 2 76例 ,铅水平 4 .4 8μg/L ,与母血铅无明显相关性。　 结论　目前北京城区孕妇血铅水平处于可接受范围。铅易于通过胎盘进入胎儿体内 ,但产妇早期乳汁中铅含量很低。另外 ,加强健康教育 ,大力治理环境 ,适当增加饮食中乳制品比例 ,采用天然气为家用燃料 ,是减少铅暴露的有效措施。 Objective To understand the present level of blood lead, umbilical cord blood lead levels and maternal milk lead levels in urban areas of Beijing, to explore the relationship between the three factors and to analyze the influencing factors of lead exposure in pregnant women. Methods According to different gestational age, pregnant women were divided into three groups: first trimester, second trimester and third trimester. Venous blood was collected from pregnant women and umbilical cord blood was collected during delivery. Maternal milk was collected after delivery. All samples were measured by graphite furnace atomic absorption method for lead content. The survey questionnaire was used to conduct surveys on the environment, lifestyle and dietary conditions of the respondents to analyze the influencing factors of lead exposure in pregnant women. Results A total of 115 maternal venous blood samples were collected. The median blood lead level during pregnancy was 3.400 μg / L. Blood lead during pregnancy showed a dynamic change, with the lowest level of 37.4 0 μg / L in the second trimester and the highest in the second trimester of pregnancy, which was 44.050 μg / L and 45.10 μg / L respectively, with a significant difference of P <0 .0 0 1. The level of education, household fuel, dairy intake of these three factors on the impact of blood lead was statistically significant. There were 4 34 cases of umbilical cord blood collected, with a median lead of 26.60 μg / L, which was positively correlated with maternal blood lead (r = 0.365, P <0.001). There were 76 cases of milk collected, the level of lead was 4.48μg / L, no significant correlation with maternal blood lead. Conclusion At present, blood lead level of pregnant women in Beijing urban area is within acceptable range. Lead easily passes through the placenta into the fetus, but low levels of maternal lead in early milk. In addition, strengthening health education, vigorously controlling the environment, increasing the proportion of dairy products appropriately, and using natural gas as domestic fuel are effective measures to reduce lead exposure.