Time Series Analysis Of Premature Rupture Of Membranes And Air Pollutants In A Hospital Of Hefei From 2017 To 2019

Objective:To learn about the occurrence of premature rupture of membranes（PROM）in the Maternal and Child Health Hospital Affiliated to Anhui Medical University,air pollutants,and meteorological conditions in Hefei from 2017 to 2019.The purpose of this study was to investigate the acute effects of air pollutants on the occurrence of PROM.Methods:From 2017 to 2019,46338 women with single pregnancy who delivered in the hospital were collected,and 10042 of them had PROM.The data of six air pollutants including PM_2.5,PM₁₀,SO₂,CO,NO₂,O₃at 10 monitoring points in the same period in Hefei were provided from the Hefei Center for Disease Control and Prevention.Daily meteorological data of Hefei,including air pressure,temperature,humidity and wind speed,were provided by China Meteorological Data Network.The data of pregnant women,air pollutants and meteorological data with daily PROM were analyzed statistically.The General Additive Model（GAM）of time series analysis method was used to analyze the association between the exposure of various air pollutants and the number of PROM cases occurring every day.Result:1.The general information of the motherFrom 2017 to 2019,a total of 46,338 singleton pregnant women were hospitalized and delivered in the hospital,of which 10,042 cases（21.67%）had PROM.The incidence of PROM was different in pregnant women with different ages,different gestational times and delivery times（P<0.001）.Pregnant women with PROM delivered fetuses of different genders,and the difference was not statistically significant（P=0.246）.The proportion of preterm PROM was significantly higher than that of full-term PROM（P<0.001）.The proportion of PROM in warm conception season was slightly higher than that in cold season,and the difference was not statistically significant（P=0.916）.The proportion of PROM in pregnant women in the cold season of delivery was slightly higher than that in warm season（P<0.001）.2.Air pollutants and meteorological data resultsFrom 2017 to 2019,the annual average daily concentration of PM_2.5,PM₁₀,SO₂,CO,NO₂and O₃in Hefei were 48.85μg/m³,73.67μg/m³,8.39μg/m³,0.83mg/m³,44.28μg/m³and 99.17μg/m³respectively.In warm season,the average daily concentration of PM_2.5,PM₁₀,SO₂,CO,NO₂and O₃were 32.95μg/m³,60.77μg/m³,7.22μg/m³,0.73mg/m³,36.31μg/m³and 123.89μg/m³respectively.In cold season,the average daily concentration of PM_2.5,PM₁₀,SO₂,CO,NO₂and O₃were 65.02μg/m³,86.79μg/m³,9.58μg/m³,0.94mg/m³,52.39μg/m³,74.04μg/m³respectively.The daily average pressure,temperature,humidity and wind speed in Hefei were respectively1012.09 h Pa,16.87℃,76.11%and 2.01m/s.3.Single pollutant modelAmong the effects of various pollutants on the number of daily occurrence of PROM,the strongest lag effect of PM_2.5was in 2 day,that is,the occurrence of PROM increased by 0.16%（ER=0.16,95%CI:0.08-0.25）for per 10 unit increase of PM_2.5concentration.The strongest lag effect of PM₁₀was in the day of outcome,and the number of PROM cases increased by 0.14%（ER=0.14,95%CI:0.06-0.21）for per 10unit increase of PM₁₀concentration.The strongest lag effect of SO₂was in 5 day,and the number of PROM cases increased by 0.85%（ER=0.85,95%CI:0.14-1.62）for per 10unit increase of SO₂concentration.The strongest lag effect of NO₂was in 5 day,that is,the occurrence of PROM increased by 0.15%（ER=0.15,95%CI:0.02-0.28）for per 10unit increase of NO₂concentration.The hysteresis effect of CO and O₃on PROM was not statistically significant during the 7 days.4.Multi-pollutant modelWhen PM₁₀and O₃were respectively included in the SO₂single pollutant model,the effect of SO₂on PROM was higher than that of the single pollutant model.When CO and PM_2.5were respectively included,the effect of SO₂on PROM decreased compared with the single pollutant model.When PM₁₀and CO were respectively included in the NO₂single pollutant model,the effect of NO₂on PROM was higher than that of the single pollutant model.When PM_2.5and O₃were respectively included,the effect of NO₂on PROM decreased compared with the single pollutant model.5.Hierarchical analysisAccording to the seasonal stratification analysis of perinatal gender and PROM occurrence,PROM was more affected by the increase of PM_2.5,PM₁₀,CO,NO₂concentration in the cold season.In warm season,PROM was susceptible to SO₂and O₃.The increase of PM₁₀、SO₂、CO、NO₂、O₃concentration had a strong effect on the occurrence of PROM in pregnant women delivering male perinatal infants.Conclusion:PM_2.5,PM₁₀,SO₂and NO₂had acute exposure and lag effects on the occurrence of PROM.Pregnant women were more likely to develop PROM under the influence of air pollutants in cold season.Male perinatal infants delivered by pregnant women with PROM were more susceptible to acute exposure to contaminants.