Department of Public Health, Guangdong Women and Children Hospital, 521 Xingnan Road, Panyu District, Guangzhou, 511442, China.
Department of Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, China.
Int J Hyg Environ Health. 2021 Jul;236:113795. doi: 10.1016/j.ijheh.2021.113795. Epub 2021 Jun 28.
Maternal exposure to fine particulate matter (PM) has been associated with a few adverse birth outcomes. However, its effect on stillbirth remains unknown in China, especially the susceptible windows and potential modifiers.
This study aimed to evaluate the associations between maternal PM exposure and stillbirth in seven Chinese cities.
We used birth cohort data of 1,273,924 mother-and-birth pairs in seven cities in southern China between 2014 and 2017 to examine these associations. Pregnant women were recruited in the cohort at their first visit to a doctor for pregnancy, and stillbirths were recorded at the time of birth. Air pollution exposures were assessed through linking daily air pollutant concentrations from nearby monitoring stations to the mother's residential community. Cox regression models were applied to determine the associations between PM and stillbirth for different gestational periods.
Among the participants, 3150 (2.47‰) were identified as stillbirth cases. The hazard ratio (HR) of stillbirths was 1.52 (95% CI: 1.42, 1.62) for each 10 μg/m increase in PM during the entire pregnancy after controlling for some important covariates. Relatively stronger associations were observed during the second trimester [adjusted HR = 1.67 (95% CI: 1.57, 1.77)] than trimesters 1 [HR = 1.44 (95% CI: 1.37, 1.52)] and trimester 3 [HR = 1.23 (95% CI: 1.16, 1.30)]. Stratified analyses also showed a stronger association among pregnant women without previous pregnancy and previous delivery experiences.
The study indicates that maternal exposure to PM, especially during the midpoint period of pregnancy, might increase the risk of stillbirths. Maternal previous pregnancy and delivery may modify this association.
母体暴露于细颗粒物（PM）与一些不良出生结局有关。然而，在中国，其对死产的影响尚不清楚，特别是易感窗口和潜在的修饰剂。
本研究旨在评估中国南方七个城市中母体 PM 暴露与死产之间的关系。
我们使用了 2014 年至 2017 年中国南方七个城市的 1273924 对母婴队列数据来研究这些关联。在妊娠的第一次就诊时，孕妇在队列中招募，在分娩时记录死产。通过将附近监测站的每日空气污染物浓度与母亲的居住社区相联系，评估空气污染暴露情况。应用 Cox 回归模型确定 PM 与不同妊娠期间死产之间的关系。
在参与者中，有 3150 例（2.47‰）被确定为死产病例。在控制了一些重要的混杂因素后，整个孕期每增加 10μg/m PM，死产的风险比（HR）为 1.52（95%CI：1.42，1.62）。与第一孕期（HR=1.44（95%CI：1.37，1.52））和第三孕期（HR=1.23（95%CI：1.16，1.30））相比，第二孕期的关联更强[调整后的 HR=1.67（95%CI：1.57，1.77）]。分层分析还表明，在没有既往妊娠和分娩经历的孕妇中，这种关联更强。
该研究表明，母体暴露于 PM，特别是在妊娠中期，可能会增加死产的风险。母体既往妊娠和分娩经历可能会改变这种关联。
