Exposure to mobile source air pollution and adverse birth outcomes in the Los Ang

描述（由研究者提供）：我们将解决先前研究空气污染与围产期结局之间关系的两个主要弱点。第一个弱点，暴露误差，将通过将一个全面的大型出生数据库与一个先进的暴露建模系统的空间和时间分辨的暴露估计联系起来来解决。第二个弱点，即对怀孕期间影响妇女个人暴露的时间活动和行为变化知之甚少，将通过使用问卷调查和GPS时间活动抽样进行前瞻性队列研究来解决。结果包括低出生体重（LBW）和早产（PTD）。对前瞻性队列的超声结果进行探索性分析。长期目标将是开发可应用于大规模人口出生研究的方法，这些研究将包括更密集的结果和暴露评估，以及母胎遗传变异评估。具体目的如下：1)通过大型回顾性队列研究，确定母亲居住暴露于交通相关空气污染物与LBW和PTD的关系。我们将研究这一出生队列（N=97,500），并提供母亲在怀孕期间的详细临床资料。每个住所的室外多环芳烃（PAH）、一氧化氮（NO）和二氧化氮（NO2）浓度将按月和三个月对每个受试者进行评估和汇总。将进行逻辑回归，以调整出生登记中通常没有的已知或可疑混杂因素。将检查子宫内易受空气污染物影响的窗口。2)测试前瞻性招募方法，并开发数据收集仪器，可用于计划中的更大规模的超声数据研究。我们将在首次产前访问期间前瞻性地招募100名受试者。受试者将在怀孕期间接受环境和行为问卷调查，并在一周内进行三次GPS采样。将评估怀孕期间时间-活动和空气污染暴露的变化。此外，将开发方法来检查空气污染与超声结果（例如头围）的关系，这可能作为子宫内生长限制的生物标志物。3)测试测量和建模方法。我们将对40名潜在受试者进行广泛的暴露测量，并开发和验证模型，以估计户外，运输和个人暴露。模型性能将成为设计更大规模研究的基础。从这项研究中产生的知识将通过识别和描述影响不良出生结果的环境因素对公共卫生有益。预期这项研究将对有关保护易受空气污染不利影响的孕妇健康的决定产生影响。

DESCRIPTION (provided by investigator): We will address two major weaknesses in previous studies examining the association of air pollution with perinatal outcomes. The first weakness, exposure error, will be addressed by linking a comprehensive and large birth database with spatially and temporally resolved exposure estimates from an advanced exposure modeling system. The second weakness, namely, minimal knowledge concerning time-activity and behavior changes that affect women's personal exposures during pregnancy, will be addressed by following a prospective cohort using questionnaires and GPS time-activity sampling. Outcomes include low birth weight (LBW) and preterm delivery (PTD). Exploratory analysis will be conducted for ultrasound outcomes in the prospective cohort. The long-term goal will be to develop methods that can be applied to a large population- based study of births that will include more intensive outcome and exposure assessments, as well as assessments of maternal-fetal genetic variation. The specific aims are as follows: 1) To determine the association of mothers' residential exposure to traffic-related air pollutants with LBW and PTD in a large retrospective cohort. We will study this birth cohort (N=97,500) with detailed clinical data for the mother during pregnancy. Outdoor concentrations of polycyclic aromatic hydrocarbons (PAH), nitric oxide (NO), and nitrogen dioxide (NO2) at each residence will be estimated and summarized by month and trimester for each subject. Logistic regression will be performed adjusting for known or suspected confounding factors not generally available in birth registries. In utero windows of vulnerability to air pollutants will be examined. 2) To test prospective recruiting methods and develop data collection instruments that can be used in a planned larger study using ultrasound data. We will prospectively recruit 100 subjects during their first prenatal visit. The subjects will be followed by an environmental and behavior questionnaire coupled with one-week GPS sampling three times during their pregnancy. Changes in time-activity and air pollution exposures during pregnancy will be assessed. In addition, methods will be developed to examine the association of air pollution with ultrasound outcomes (e.g. head circumference), which may serve as biomarkers of in utero growth restrictions. 3) To test measurement and modeling methods. We will conduct extensive exposure measurements for 40 of the prospective subjects, and models will be developed and validated to estimate outdoor, in-transit and personal exposures. Model performance will form the basis for the design of a larger study. PUBLIC HEALTH RELEVANCE The knowledge that will emerge from this study will be of benefit to public health by identifying and describing environmental factors affecting adverse birth outcomes. This research is expected to have an impact on decisions regarding the protection of health in pregnant women who are susceptible to the adverse effects of air pollution.