Abstract
BackgroundSome studies have reported that air pollution exposure can have adverse effects on pregnancy outcomes. However, the disparity between urban and rural areas in the risk of preterm birth (PTB) has yet to be elucidated. Considering geographic contexts as homogeneous or ignoring urban–rural differences cannot accurately reveal the disparities in the health effects of air pollution under different geographic contexts. The aims of this study were to examine the disparities in the risks of PTB in three different regions and five urban–rural types and to investigate the extent to which fine particulate matter (PM2.5) exposure during the entire pregnancy can explain the variations.MethodsWe collected data on 429,865 singleton newborns born in 2014 in Hubei Province, China, and divided Hubei Province into three regions. Spatial correlation methods were employed to measure the associations between the rate of PTB and air pollution using average annual indexes for the entire province and regions. A series of multilevel logistic models were conducted to examine disparities in the risks of PTB with decreases in urbanity and the effects of air pollution exposure on the occurrence of preterm births.ResultsThe PM2.5 concentration was significantly different across the regions. The eastern region had the most wide-ranged and serious level of pollution, whereas the levels in the middle and western regions weakened. The odds of PTB and air pollution exhibited a positive spatial correlation for the entire province and in the east (BiMoran’s I = 0.106 and 0.697, respectively). Significant urban–rural disparities in the risks of PTB were noted in the east and middle regions, and the mean PM2.5 exposure during the entire pregnancy was positively associated with PTB risk. However, in the west, the results showed weak differences in the risks of PTB among the five urban–rural types and an insignificant effect of PM2.5 exposure. The direction of the effect of district/county-level income on PTB varied by region.ConclusionsThis study finds that air pollution exposure and PTB have significant and positive spatial relationships in areas with a serious air pollution burden. The risks of PTB in three regions of Hubei Province follow the same W-shaped pattern as urbanity decreases and rurality increases. High levels of air pollution exposure may be an important disadvantage for urban pregnant women in this setting.
Highlights
Some studies have reported that air pollution exposure can have adverse effects on pregnancy outcomes
This study aims to explore the relationships between air pollution and the risks of preterm birth (PTB) as well as the risk disparities across different regions and urban–rural continua
Multilevel models further demonstrated that the risk of PTB increased by 12% for a 30-μg/m3 increase in average PM2.5 exposure during pregnancy after controlling for covariates and urban–rural variables in the east, while no significant correlation was found in other cases
Summary
Some studies have reported that air pollution exposure can have adverse effects on pregnancy outcomes. The aims of this study were to examine the disparities in the risks of PTB in three different regions and five urban–rural types and to investigate the extent to which fine particulate matter (PM2.5) exposure during the entire pregnancy can explain the variations. Considerable research has explored the relationships between maternal air pollution exposure and various adverse outcomes, such as preterm birth (PTB), low birth weight (LBW), and small for gestational age (SGA). While some studies showed that long-term or short-term maternal exposure during pregnancy had positive influences on adverse delivery outcomes [5, 21,22,23,24,25], other studies found insignificant relationships [26] or even negative associations [27]
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
