Characterization of the vaginal microbiome of Brazilian women in reproductive age

Abstract

Studies on the vaginal microbiome have started only recently, following the researches for characterizing the human microbiome. Describing the real composition of microbial community in the vagina by microbiome studies is crucial for women's health, since abnormal vaginal microbiota is associated with poor pregnancy outcome and increased risk for acquisition of sexually transmitted infections. Up to now, the most important study on vaginal micobiome was performed on samples from North-American women. It was demonstrated that although the vaginal microbiota is variable and dynamic, it could be placed into one of 5 communities, according to the types and abundance of the species present. The major part of the vaginal communities from women experiencing bacterial vaginosis (BV) is placed in one of the 5 types of communities that is characterized by lower load of lactobacillus species. This community can be divided in 3 sub-communities, according to the interactions among certain bacterial species. To date, no study has been performed aiming to determine the vaginal microbiome of Brazilian women. Considering the heterogeneity on hygiene practices and sexual behavior, as well as the high prevalence of gynecological and obstetrical complications among Brazilian women, the objective of this study is to characterize the vaginal microbiome of Brazilian women from the five regions of the country. Bacterial species and their abundance will be determined by pyrosequencing a region of the 16S rRRNA gene. Classification of the vaginal microbiota will be also performed according to Nugent's criteria in Normal, Intermediate and BV, on Gram-stained smears. Sub-communities of bacterial species will be assessed on cases of BV. Total bacterial cunt by flux cytometry will be performed on vaginal samples from women presenting bacterial vaginosis. Samples will be also submitted to correlation tests between presence of certain sub-communities and total bacterial count, when BV is detected. Thus, these results will allow the first-time description of the vaginal microbiome in Brazilian women and may contribute to future strategies for improving women's reproductive health. (AU)