Vagina and its natural microbiota form a balanced ecosystem. Any disruption of this ecosystem can lead to destabilisation and infection. Lactobacilli colonisation is believed to be beneficial since it prevents other microorganisms from colonizing the vaginal epithelium via competitive adhesion, interactions with the local immunity and the production of lactic acid, hydrogen peroxide and antibacterial substances. Lactobacilli constitute an important part of the urogenital tract microbiota. And the lactobacilli-dominated vaginal microbiome is a major determinant for female urogenital health.