Preliminary Study On The Impacts Of Maternal Air Pollution Exposure On Preterm Birth And Low Birth Weight In Shijiazhuang

Objective: To explored the impacts of maternal air pollution exposure on Preterm birth(PB)and low birth weight(LBW)in Shijiazhuang city.Methods: 1 Population studies 1.1 The pregnant women data and the birth data of newborns were obtained from the Fourth Hospital of Hebei Medical University from August 1,2013 to December 31,2017.1.2 The daily air pollution records from 2014 to 2017,including the Air Quality Index(AQI),PM2.5,inhalable particulate matter(aerodynamic diameter?10?m,PM10),sulfur dioxide(SO2),nitrogen dioxide(NO2),carbon monoxide(CO)and ozone(O3),were collected? 1.3 The average exposure level of each pollutant during gestation and each trimester for each birth was calculated.2 Animal experiment Pregnant Sprague–Dawley rats were exposure to concentrated PM2.5 by Air Fine Particulate Matter Online Enrichment System.The weight of each neonatal rat was measured to observed the effects of PM2.5 on the birth weights of offspring of rats.3 Statistical analysis Data were analyzed with R3.4.1 statistical software to explored the impacts of each air pollution exposure on(PB)and LBW.Results: 1.Population studies 1)There were 3407 pregnant women during the study time period.The total premature births was 430,and the PB rate was 12.62%.The average birth weight was(3184.62±563.92)g,and LBW infants was 324 and the LBW rate was 9.51%.2)In PB group,the average exposure levels of AQI,PM2.5,PM10,SO2,NO2 and O3 during first trimester,the levels of PM2.5,PM10,SO2 during second trimester,the levels of PM2.5,SO2 during pregnancy were significantly higher than that of the normal group(P<0.05,P<0.01).3)Impact of maternal air pollution exposure on PB The results of logistic regression analysis showed that PM2.5 exposure(first trimester,pregnancy),PM10 exposure(first trimester,second trimester and pregnancy),SO2 exposure(first trimester,second trimester and pregnancy)and NO2 exposure(first trimester)will increased the occurrence of PB.4)The results of linear multivariable models indicated that maternal exposure to the studied all pollutants in the first trimester showed negative effects on birth weight.A decrease of 26.6,7.2,4.4,5.7,8.1,2.8,6.0g in birth weight was associated with an increase of 10 unit in the average level of AQI,PM2.5,PM10,SO2,NO2,CO and O3 during the first trimester respectively;A decrease of 12.7,6.3,4.7g in birth weight was associated with an increase of 10 unit in the average level of PM2.5,PM10 and SO2 respectively;A decrease of 1.3g in birth weight was associated with an increase of 10 unit in the average level of SO2 respectively;A decrease of 8.3,6.3,5.5,1.3g in birth weight was associated with an increase of 10 unit in the average level of PM2.5,PM10,SO2,NO2 respectively.2.Animal experiment The average birth weight of neonatal rats in PM2.5 exposure group was(10.33±1.21)g which was significantly lower than that[(11.33±1.63)g] of control.It indicated that the maternal PM2.5 exposure during pregnancy would affect the birth weight of neonatal rats and reduce the birth weight.Conclusions: 1.There is an association between maternal air pollution exposure and adverse birth outcomes including PB and LBW.Maternal air pollution exposure can significantly increase the risk of PB and decrease the birth weight of newborns.2.The effect of maternal air pollution exposure on LBW may be more significant than that of PB.3.The adverse effects of the exposure of PM2.5,PM10 or SO2 on PB and LBW are more harmful.4.The first and second trimester may be the critical period for maternal air pollution to affect PB and LBW.5.The effects of maternal air pollution exposure of O3,CO and AQI on PB are not observed.