Effect of the pattern of colonization of the maternal genital tract at the time of delivery on early onset neonatal sepsis

Early onset neonatal sepsis increases significantly in the presence of vaginal and cervical colonization with pathogenic organisms. The aim of this study was to study the effect of the pattern of colonization of the maternal genital tract at the time of delivery on early onset neonatal sepsis. A prospective clinical study was conducted in Cairo University Hospitals on 352 pregnant women coming for delivery and their newborns. Vaginal swabs were taken from the mothers before first vaginal examination [PV] and just before delivery. Surface swabs from the body of babies were taken. The neonates were clinically evaluated and prospectively followed up in the first week of their life for clinical evidence of sepsis and blood cultures were done for clinically septic neonates. Swabs were taken from different environmental sources in the Obstetric and Neonatology wards. Microbiological typing was conducted by biotyping and antibiogram to prove the similarity between microorganisms isolated from maternal or environmental sources and the corresponding neonates. Pulsed field gel electrophoresis was used for genotyping of phenotypically similar isolates. Microbiological similarity between culture results of mothers and their newborns was proven in 86% of cases. The correlation between clinical sepsis and microbiological agreement was also highly significant [p value=0.001]. Positive vaginal swab cultures were highly predictive of positive blood culture [p-value=0.09]. We found that, multiple vaginal examinations [more than 3 times] was the most frequent maternal risk factor of neonatal bacteremia [p-value=0.049]. Contamination of environment [gel and gloves] and equipment [suction sets] used for mothers and their babies during delivery was probably an important source of microorganisms. Maternal colonization and the contaminated environment were important risk factors for neonatal sepsis. Hence, limitation of PV and strict infection control measures should be followed in delivery room