The microbiome: a determinant of reproductive health and fitness?

There is a growing appreciation of the importance played by the reproductive tract microbiome in shaping fertility and reproductive health. Historically viewed as a microbially simple niche, the lower female reproductive tract is now recognized to harbor dynamic microbial communities that interact with host physiology to influence fertility, pregnancy outcomes, and reproductive disorders. Increasing evidence also implicates the comparatively low-biomass microbiomes of the upper female reproductive tract and the male reproductive tract in reproductive health. This Views and Reviews special edition is made up of four articles that critically examined the ecological drivers of vaginal microbiota composition, the strengths and limitations of current microbiome assessment tools in fertility care, links between dysbiosis and female reproductive disorders, and emerging evidence implicating the male reproductive microbiome in sperm function and fertility. Collectively, these contributions highlighted both the promise and the current limitations of microbiome-informed reproductive care, underscoring the need for rigorous, standardized, and outcome-focused research to support clinical implementation.