The Generation R Study Group, Erasmus Medical Center, Rotterdam, The Netherlands.
Environ Health. 2009 Dec 22;8:59. doi: 10.1186/1476-069X-8-59.
The effects of ambient air pollution on pregnancy outcomes are under debate. Previous studies have used different air pollution exposure assessment methods. The considerable traffic-related intra-urban spatial variation needs to be considered in exposure assessment. Residential proximity to traffic is a proxy for traffic-related exposures that takes into account within-city contrasts.
We investigated the association between residential proximity to traffic and various birth and pregnancy outcomes in 7,339 pregnant women and their children participating in a population-based cohort study. Residential proximity to traffic was defined as 1) distance-weighted traffic density in a 150 meter radius, and 2) proximity to a major road. We estimated associations of these exposures with birth weight, and with the risks of preterm birth and small size for gestational age at birth. Additionally, we examined associations with pregnancy-induced hypertension, (pre)eclampsia, and gestational diabetes.
There was considerable variation in distance-weighted traffic density. Almost fifteen percent of the participants lived within 50 m of a major road. Residential proximity to traffic was not associated with birth and pregnancy outcomes in the main analysis and in various sensitivity analyses.
Mothers exposed to residential traffic had no higher risk of adverse birth outcomes or pregnancy complications in this study. Future studies may be refined by taking both temporal and spatial variation in air pollution exposure into account.
环境空气污染对妊娠结局的影响仍存在争议。先前的研究使用了不同的空气污染暴露评估方法。在暴露评估中需要考虑到城市内交通相关的空间变异。居住与交通的接近程度是交通相关暴露的一个指标，考虑到了城市内的差异。
我们在一项基于人群的队列研究中，调查了 7339 名孕妇及其子女的居住与交通接近程度与各种出生和妊娠结局之间的关联。居住与交通的接近程度定义为 1）150 米半径内的距离加权交通密度，和 2）接近主要道路。我们估计了这些暴露与出生体重、早产和出生时小于胎龄儿的风险之间的关联。此外，我们还研究了与妊娠高血压、（先兆）子痫和妊娠期糖尿病的关联。
距离加权交通密度差异较大。近 15%的参与者居住在距离主要道路 50 米以内的地方。在主要分析和各种敏感性分析中，居住与交通的接近程度与出生和妊娠结局均无关联。
在本研究中，暴露于居住交通的母亲没有更高的不良出生结局或妊娠并发症风险。未来的研究可能需要考虑到空气污染暴露的时间和空间变化来进行改进。
