Study On The Relationship Between Antibiotic Therapy In The Third Trimester And Pregnancy Outcome Of GBS Infection

【Background】Group B Streptococcus(GBS)is a facultative anaerobe mainly colonized in the digestive tract and urogenital tract of healthy people.It belongs to Gram-positive bacteria and is latent.About 10%-30%of pregnant women will be infected with GBS if effective measures are not taken.Among them,50%will spread the infection to the newborn,which is one of the important causes of infection-related diseases during pregnancy,puerperal infection and neonatal infection.GBS infection can lead to maternal infectious diseases,such as chorioamnitis,postpartum endometritis,genital tract inflammation and urinary tract infection,resulting in neonatal bacteremia,meningitis,and even death in severe cases.GBS infection occurring in newborns within the first week after birth is called GBS early-onset disease(GMS-EOD),which is mostly caused by vertical mother-to-child transmission during delivery or after membrane rupture.About 1%to 2%of newborns exposed to GBS will develop GBS-EOD,and the mortality rate is about 2.1%for sick term infants and 19.2%for premature infants.If the infection occurs from 1 week to 2 to 3months after birth,it is called late-onset B-streptococcal disease(GBS-LOD),which is mostly due to horizontal transmission from mother to child or contact with other infectious sources inside and outside the hospital.The mortality rate of the infants is 3.4%in term infants and 7.8%in premature infants,respectively.In recent years,more and more attention has been paid to the monitoring of GBS infection in pregnant women in the third trimester,and the prophylactic and normative use of antibiotics during childbirth has been formulated through statistics and drug sensitivity analysis,so as to achieve the purpose of preventing group B streptococcal disease in newborns.According to current data analysis from around the world,prophylactic use of antibiotics during childbirth has effectively reduced the incidence of group B streptococcus in newborns,reduced the perinatal infection rate of pregnant women and greatly improved maternal and infant outcomes.Therefore,the use of antibiotics is very important for pregnant women with GBS infection in late pregnancy.【Objective】To explore the effect of prophylactic oral antibiotic therapy on pregnancy outcome of pregnant women infected with GBS.【Methods】A total of 3975 pregnant women who were tested for GBS in the Second Affiliated Hospital of Guangzhou Medical University from January 2021 to December 2022 were selected in a prospective case-control study,and 369 of them were GBS positive.A total of 187 GBS positive cases with standardized labor examination,smooth delivery,complete data and completed follow-up in our hospital were selected as the research object,and 195 GBS negative cases with delivery at the same time were selected as the control group,which was divided into 6 groups.Group 1:There were 187 positive cases in the study group(GBS+)and 195 negative cases in the control group(GBS-).The second group:without antibiotic treatment(Non-Antibiotic,NA)GBS positive cases(GBS+NA)51 cases as the study group,GBS negative cases without antibiotic prophylaxis during delivery(GMS-NA)93 cases as the control group.Group 3:Among GBS positive cases,109 pregnant women who received IAP(GBS+IAP)were the study group,and 51 pregnant women who did not receive antibiotic therapy(GBS+NA)were the control group.Group 4:A total of 50 cases of GBS Antibiotic Prophylaxis(GBS+IAIAP)were the study group and 59 cases of GBS positive patients(GBS+IAIAP)were the control group.Group 5:Antibiotic Therapy in Late Pregnancy(ATLP)20 cases(GBS+IAP+ATLP)were studied group,109 cases of GBS+IAP without ATLP were control group.Group 6:GBS positive patients receiving ATLP alone(GBS+ATLP)7 cases were the study group and GBS+IAP was the control group.Clinical data of enrolled cases were collected,including general data:age,gestational time,urinary tract infection,leucorrhea,etc.Prenatal conditions:amniotic fluid characteristics,whether there is premature rupture of membranes,premature delivery and puerperal infection,etc.Within one week after delivery:neonatal infection with jaundice,neonatal infection,etc.,and enrolled cases were tracked by electronic medical records and followed up by telephone from February to March.Use a unified questionnaire to collect the required data,and then review the data.SPSS25.0 statistical software was used to conduct statistical analysis of the data required during the entire research process.Expressed as a ratio or component ratio of data,usingχ~2Test for comparative analysis toα=0.05 is the inspection level.If the results of statistical analysis data processing show P<0.05,it indicates that the difference between the two is statistically significant.【Results】1.The rate of GBS infection in women during the third trimester of pregnancy in this region is 9.8%.There was no significant difference between the GBS positive group and the negative group in terms of age,number of miscarriages,number of births,presence or absence of urinary tract infection,presence or absence of fungal vaginitis,and leucorrhea cleanliness(P<0.05).2.In study group 2 and control group 2,there were significant differences in puerperal infection,elevated neonatal inflammatory indicators(early onset)and neonatal jaundice(P<0.05).There was no statistically significant difference in the incidence of other indicators.3.There was a statistically significant difference in the incidence of amniotic fluid contamination,increased neonatal inflammatory indicators(early onset),and neonatal jaundice between study group 3 and control group 3(P<0.05);There was no statistically significant difference in the incidence of other indicators.4.There was no statistically significant difference in the incidence of premature rupture of membranes,amniotic fluid contamination,premature delivery,neonatal fever(early onset),elevated neonatal inflammatory indicators(early onset),and neonatal infection(delayed onset)between the full IAP group and the insufficient IAP group,namely the study group and the control group.The incidence of puerperal infection and neonatal jaundice was statistically significant between the two groups.5.There were no statistically significant differences in the incidence of premature rupture of membranes,amniotic fluid contamination,premature delivery,neonatal fever(early onset),elevated neonatal inflammatory indicators(early onset),neonatal jaundice and neonatal infection(delayed onset)in study group 5 and control group 5.The incidence of puerperal infection in the two groups was statistically significant.6.In the GBS positive group,55.6%of the pregnant women who received oral sensitive antibiotics in the third trimester had negative GBS.There was no significant difference in the incidence of premature rupture of membranes,amniotic fluid contamination,premature delivery,puerperal infection,neonatal fever(early onset)and neonatal jaundice between study group 6 and control group 6.In the incidence of elevated neonatal inflammatory indicators(early onset)and neonatal infection(delayed onset),the calculated P value was less than 0.05,indicating a statistically significant difference between the two groups.【Conclusions】1.Oral antibiotic treatment in the third trimester of pregnancy,when GBS infection is identified,can reduce the incidence of puerperal infection.2.Prophylactic use of antibiotics in pregnant women infected with GBS at the time of delivery can reduce the incidence of amniotic fluid contamination in the perinatal period,elevated neonatal inflammatory indicators(early onset)and neonatal jaundice.3.It is better to use antibiotics more than 4 hours before delivery for pregnant women infected with GBS in late pregnancy to prevent puerperal infection and neonatal jaundice.