晚孕期孕妇生殖道B族链球菌感染对母儿结局的影响

Effect of group B Streptococcus infection in genital tract of pregnant women in third trimester on maternal and infant outcomes

目的探讨晚孕期孕妇生殖道B族链球菌(GBS)感染的影响因素及其对母儿结局的影响。方法选择2016年8月至2018年8月,在苏州高新区人民医院进行产前检查,并于35~37孕周时采取荧光定量PCR进行GBS DNA检测的1149例晚孕期孕妇为研究对象。采用回顾性分析方法,将其分为研究组(n=81,GBS DNA呈阳性)与对照组(n=1068,GBS DNA呈阴性)。对研究组GBS感染孕妇,采取产时抗菌药物预防(IAP)措施。收集2组受试者年龄、受教育程度、孕次、产次、流产史、分娩方式,分娩孕龄与人体质量指数(BMI)、血清维生素D含量,妊娠期糖尿病(GDM)、胎膜早破与产后出血发生情况,以及研究组新生儿出生后第4周GBS感染随访结果,并采用成组t检验、Mann-Whitney U检验、χ^(2)检验等进行统计学比较。采用多因素非条件logistic回归分析,对晚孕期孕妇GBS感染影响因素进行分析。本研究遵循的程序符合2013年新修订的《世界医学协会赫尔辛基宣言》要求,并通过苏州高新区人民医院伦理委员会审批(审批文号:[2016]伦审批第001号)。结果①2组孕妇中,初产妇与经产妇构成比、流产史、GDM发生率、血清维生素D含量比较,差异均无统计学意义(P>0.05),而2组孕妇年龄、受教育程度构成比与分娩时BMI分别比较,差异均有统计学意义(t=-2.004、P=0.045,χ^(2)=69.972、P<0.001,t=7.054、P<0.001)。②晚孕期孕妇GBS感染影响因素的多因素非条件logistic回归分析结果显示,分娩时BMI≥25 kg/m 2与受教育程度为高中及以下,均为晚孕期孕妇GBS感染的独立危险因素(OR=2.901、6.137,95%CI:1.782~4.722、3.737~10.078,均为P<0.001)。③研究组孕妇产褥期感染、新生儿肺炎发生率分别为3.7%(3/81)与4.9%(4/81),分别显著高于对照组的0.8%(9/1068)与1.0%(11/1068),并且差异均有统计学意义(P=0.047,χ^(2)=6.150、P=0.013)。④研究组孕妇分娩的81例新生儿的出生后1周GBS阳性率为53.1%(43/81),早发型GBS肺炎发生率为2.5%(2/81)。结论分娩时孕妇BMI≥25 kg/m 2与受教育程度为高中及以下,均为其GBS感染的独立危险因素。晚孕期孕妇GBS感染可导致其产褥期感染及新生儿肺炎发生率增高。

Objective To explore influencing factors of group B Streptococcus(GBS)in genital tract of pregnant women in third trimester and its effects on outcomes of pregnant women and infants.Methods From August 2016 to August 2018,a total of 1149 pregnant women in third trimester who received prenatal examination in People′s Hospital of Suzhou High-tech Zone and detection of GBS DNA by fluorescence quantitative PCR at gestational age of 35-37 weeks were selected as research subjects.By retrospective analysis method,they were divided into study group(n=81,GBS DNA^(+)in genital tract),and control group(n=1068,GBS DNA-in genital tract).Measures of intrapartum antibiotic prophylaxis(IAP)was taken to subjects in study group.Clinical data of 2 groups such as age,educational background,gravidity,parity,history of abortion,mode of delivery,gestational age and body mass index(BMI)at delivery,serum vitamin D levels,rates of gestational diabetes mellitus(GDM),premature rupture of membranes,postpartum hemorrhage,and follow-up of GBS infection of neonates in study group at 4 weeks after birth were collected.Independent-samples t test,Mann-Whitney U test and chi-square test were used for statistical comparisons.Multivariate unconditional logistic regression analysis was used to analyze influencing factors of GBS infection in genital tract of pregnant women in third trimester.The procedure in this study was in line with the requirements of Helsinki Declaration of the World Medical Association revised in 2013,and has been approved by the Ethics Committee of People′s Hospital of Suzhou High-tech Zone(Approval No.2016-001).Results①There were no statistically significant differences in composition ratio of primipara and multipara,history of abortion,incidence of GDM and serum vitamin D levels between two groups(P>0.05).While there were statistically significant differences in age,composition ratio of educational background and BMI at delivery between two groups(t=-2.004,P=0.045;χ^(2)=69.972,P<0.001;t=7.054,P<0.001).②Multivariate unconditional logistic regression analysis showed that BMI≥25 kg/m 2 at delivery and high school education level or below were independent risk factors for GBS infection in genital tract of pregnant women in third trimester(OR=2.901,6.137,95%CI:1.782-4.722,3.737-10.078,all P<0.001).③The incidence of puerperium infection and neonatal pneumonia in study group were 3.7%(3/81)and 4.9%(4/81),which were significantly higher than those in control group 0.8%(9/1068)and 1.0%(11/1068),respectively,and both differences were statistically significant(P=0.047;χ^(2)=6.150,P=0.013).④Among 81 neonates of study group,positive rate of GBS at 1 week after birth was 53.1%(43/81).The incidence of early onset GBS pneumonia in neonates was 2.5%(2/81).Conclusions BMI≥25 kg/m 2 at delivery and high school education level or below are independent risk factors for GBS infection in genital tract of pregnant women in third trimester,and may lead to increased incidence of puerperium infection and neonatal pneumonia.