Vaginal microbial flora and outcome of pregnancy

Background The vaginal microflora of a healthy asymptomatic woman consists of a wide variety of anaerobic and aerobic bacterial genera and species dominated by the facultative, microaerophilic, anaerobic genus Lactobacillus . The activity of Lactobacillus is essential to protect women from genital infections and to maintain the natural healthy balance of the vaginal flora. Increasing evidence associates abnormalities in vaginal flora during pregnancy with preterm labor and delivery with potential neonatal sequelae due to prematurity and poor perinatal outcome. Although this phenomenon is relatively common, even in populations of women at low risk for adverse events, the pathogenetic mechanism that leads to complications in pregnancy is still poorly understood. Objective This review summarizes the current knowledge and uncertainties in defining alterations of vaginal flora in non-pregnant adult women and during pregnancy, and, in particular, investigates the issue of bacterial vaginosis and aerobic vaginitis. This could help specialists to identify women amenable to treatment during pregnancy leading to the possibility to reduce the preterm birth rate, preterm premature rupture of membranes, chorioamnionitis, neonatal, puerperal and maternal–fetal infectious diseases. Conclusions Vaginal ecosystem study with the detection of pathogens is a key instrument in the prevention of preterm delivery, pPROM, chorioamnionitis, neonatal, puerperal and maternal-fetal infections.