AMBIENT AIR POLLUTION EXPOSURE DURING PREGNANCY AND LONGITUDINAL FETAL GROWTH

越来越多的研究强调了空气污染物暴露与出生时估计的胎儿生长之间的负相关[1，2]，但人体测量出生数据不能评估胎儿生长模式。此外，出生体重并不能清楚地反映胎儿生长受限[3]。尤尼斯·肯尼迪·施莱弗国家儿童健康与人类发展研究所(NICHD)的胎儿生长研究不仅拥有大量低风险单身、肥胖和双胎妊娠的纵向生长数据，还发现在单身低风险组中，美国四个种族之间的胎儿生长发育存在显著差异[4]。在美国，暴露于空气污染[5]和妊娠高血压疾病[6]都因母亲的种族/民族而异。这创造了一个独特的机会，可以调查与种族/民族环境暴露有关的胎儿生长的潜在差异，以及探索改变生长的潜在生物机制。超声测量被用来评估空气污染物对胎儿发育的影响，但很少有纵向数据，以前的研究已经有1-3个测量方法，而我们研究中的6个测量方法是可用的。这一详细的纵向数据将使我们能够突出胎儿生命期间对环境污染物的潜在敏感期。 我们的总体目标是研究产前空气污染暴露与胎儿纵向生长的关系，包括使用NICHD胎儿生长研究超声测量估计胎儿体重、胎儿身体成分和器官体积。我们还将调查临床孕妇血压和子宫动脉多普勒结果，以提供对潜在生物机制的见解。为了实现这一目标，我们建议从所有NICHD胎儿生长研究队列(单身、双胞胎和肥胖)收集住宅邮政编码数据，与国家癌症研究所(NCI)内部研究计划合作，对这些邮政编码质心进行地理编码，并利用现有数据并与NCI的空间建模人员合作，开发空气污染暴露情景。已经审查了原始研究同意书，NICHD不允许持有个人身份信息，如地址，但允许邮政编码。NIH机构审查委员会已将其确定为非人类受试者研究(见附录1)。

An increasing number of studies highlight an inverse association between air pollutant exposure and fetal growth estimated at birth [1, 2], but anthropometric birth data does not allow assessment of fetal growth patterns. Furthermore, birth weight does not clearly reflect fetal growth restriction [3]. The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Fetal Growth Studies not only have longitudinal growth data on a large number of low-risk singleton, obese and dichorionic twin pregnancies, but also found significant differences in fetal growth among four US ethnic groups in the singleton low-risk group [4]. Both air pollution exposure [5] and hypertensive disorders of pregnancy [6] vary by maternal race/ethnicity in the US. This creates a unique opportunity to investigate potential variations in fetal growth related to environmental exposure by race/ethnicity as well as to explore potential biologic mechanisms for altered growth. Ultrasound measurements have been used to assess the effects of air pollutants on fetal development but rarely with longitudinal data, and prior studies have had 1-3 measures available compared to the six measures during pregnancy in our study. This detailed longitudinal data will allow us to highlight potential periods of sensitivity to environmental contaminants during fetal life. Our overall goal is to study the association of prenatal air pollution exposure on longitudinal fetal growth including estimated fetal weight, fetal body composition and organ volumes using NICHD Fetal Growth Studies ultrasound measurements. We will also investigate clinical maternal blood pressure and uterine artery Doppler results to provide insights into potential biologic mechanisms. To accomplish this, we propose to assemble the residential zip code data from all NICHD Fetal Growth Study cohorts (singleton, twin and obese), geo-code those zip code centroids in collaboration with the National Cancer Institute (NCI) Intramural Research Program and develop air pollution exposure scenarios using existing data and in collaboration with spatial modelers at NCI. Original study consent forms have been reviewed and the NICHD is not permitted to hold personally identifiable information, such as address, but zip codes are permitted. This has been determined to be Non-Human Subjects Research by the NIH Institutional Review Board (see Appendix 1).