The effects of group B streptococcus colonization during late pregnancy on vaginal microbiota and neonatal outcomes / 中国新生儿科杂志

ABSTRACT

Objective:To study the effects of group B streptococcus (GBS) colonization during late pregnancy on vaginal microbiota and neonatal outcomes.Methods:From September 2020 to September 2021, pregnant women receiving prenatal care and delivered in our hospital were prospectively enrolled. They were assigned into GBS(+) group and GBS(-) group based on the results of GBS culture and/or PCR tests of vaginal secretions. The mothers were also assigned into early-onset infection(EO) group and non-early-onset infection(non-EO) group based on the presence or absence of early-onset infection of their neonates. The vaginal microbiota and neonatal outcomes were compared between these groups.Results:A total of 125 cases were enrolled, including 65(52.0%) in GBS(+) group and 60(48.0%) in GBS(-) group. 24 cases (19.2%) were in EO group and 101 cases (80.8%) in non-EO group. The incidences of premature rupture of membranes (PROM), amniotic fluid contamination, chorioamnionitis and early-onset neonatal infection in GBS(+) group were significantly higher than GBS(-) group(all P<0.05).The abundances of Streptococcus and Ureaplasma in vaginal flora of GBS(+) group were higher than GBS(-) group ( P<0.01), whereas Rhodococcus, Phyllobacterium and Bifidobacterium were lower than GBS(-) group ( P<0.05).The EO group had significantly higher abundance of enterococcus than the non-EO group ( P<0.05). Mothers with GBS colonization and neonates with early-onset infection had the highest abundance of Escherichia/Shigella ( P=0.04). Mothers with GBS colonization and neonates without early-onset infection showed the highest abundance of Gardnerella ( P=0.04). Conclusions:GBS colonization during late pregnancy increases the incidences of PROM, amniotic fluid contamination, chorioamnionitis and early-onset neonatal infection. GBS colonization causes abnormal vaginal flora in pregnant women. The increases of Ureaplasma, Streptococcus, Escherichia/Shigella and Enterococcus in vaginal microbiota maybe associated with early-onset neonatal infection.