Vaginal Microbiome in Reproductive Medicine

Abstract

The human microbiome has been given increasing importance in recent years. The establishment of sequencing-based technology has made it possible to identify a large number of bacterial species that were previously beyond the scope of culture-based technologies. Just as microbiome diagnostics has emerged as a major point of focus in science, reproductive medicine has developed into a subject of avid interest, particularly with regard to causal research and treatment options for implantation failure. Thus, the vaginal microbiome is discussed as a factor influencing infertility and a promising target for treatment options. The present review provides an overview of current research concerning the impact of the vaginal microbiome on the outcome of reproductive measures. A non-Lactobacillus-dominated microbiome was shown to be associated with dysbiosis, possibly even bacterial vaginosis. This imbalance has a negative impact on implantation rates in assisted reproductive technologies and may also be responsible for habitual abortions. Screening of the microbiome in conjunction with antibiotic and/or probiotic treatment appears to be one way of improving pregnancy outcomes.

Optimal sampling and analysis methods for clinical diagnostics of vaginal microbiome

“…Vaginal microbial composition is a potential future target for clinical diagnostics [10,20,24,[28][29][30]. However, the development of any diagnostic test in clinical microbiology requires straightforward and trustworthy sample-collection methods.…”

“…Lactobacilli protect women from pathogenic microbes. The development of imbalanced microbiota composition leads to a pathological condition called dysbiosis, a state which has been linked to various disorders and diseases typical for the urogenital tract [6][7][8][9][10]. For example, anaerobic bacteria such as Gardnerella, Atopobium, and Prevotella spp.…”

“…For example, anaerobic bacteria such as Gardnerella, Atopobium, and Prevotella spp. are shown to dominate microbiota in bacterial vaginosis and increase the risk of vaginal and urogenital infections as well as various sexually transmitted infections (STI) [9][10][11][12][13].…”

“…Conventionally, vaginal microbiota has been analyzed by light microscope with direct staining of pap smear or by traditional cultivation methods. Today, next-generation sequencing (NGS) is the method of choice for analyzing clinical human microbiota samples [1,10,17,18]. Thus, the current era of microbiological research is characterized by its reliance on large data sets of nucleotide sequences and bioinformatics [17,18].…”

“…Thus, the current era of microbiological research is characterized by its reliance on large data sets of nucleotide sequences and bioinformatics [17,18]. NGS-based molecular analysis methods have increased our knowledge of the detailed vaginal microbial community composition and have provided a broader view of the microbial factors that influence the health of this rather complex vaginal ecosystem [1,10]. Utilization of NGS as a tool in clinical diagnostics and treatment is currently under heady investigation [10,[18][19][20].…”