Female reproductive tract microbiome in gynecological health and problems

Microbes are intimately associated with human existence and health. Gut, oral cavity, skin, respiratory and urinogenical tracts are the major body sites inhabited by large consortia of microorganisms; each with specific composition. Application of high throughput genomic technologies has paved ways to gain an improved knowledge about the composition of the resident microbes and the ecosystem homeostasis and underscores the concept that dysbiosis of the flora may lead to predisposition to infection and diseases. Successful human reproduction owes an immense debt to this microbial community. Microbial communities exist throughout the entire length of the female reproductive tract at variable composition and density and play a role in gametogenesis, reproductive cyclicity, pregnancy and successful delivery of newborns. This review focuses on the recent studies from all over the globe on the composition of microflora in the female reproductive tract, their spatio-temporal diversity across the age of women and how the host–microbe collaboration is pursued to maintain reproductive efficiency. A special emphasis has been placed on the disruption of the stable flora and its association with the microbial imbalance and infections in bacterial vaginosis, endometriosis and pre-term birth. Finally, this article highlights that the restoration of normal microbial flora might provide a long-term therapeutic measure for the reproductive failures and endow with solutions to the global problem of reproductive failure, preterm birth and neonatal deaths.