Shaping the Female Microbiome: A Review of Lifestyle Factors Influencing the Vaginal, Gut, Oral, and Skin Microenvironments

The female microbiome, spanning the vaginal, gut, oral, and skin sites, harbours distinct microbial communities. Although the diversity and function of microbial communities across these sites are becoming increasingly understood, the extent to which modifiable lifestyle and environmental factors such as smoking, diet, alcohol intake, obesity, physical activity, stress, hygiene, and sexual behaviours shape these microbiomes remains underexplored. This review is restricted to modifiable lifestyle and environmental factors and does not comprehensively assess pharmaceutical exposures (e.g., antibiotics or hormonal therapies) or hormonal influence. To date, no review has comprehensively assessed and compiled evidence across the four microbial sites in females, despite their unique hormonal, physiological, and reproductive characteristics that distinctly influence microbial composition and function. This review provides a comprehensive examination of how such factors influence the dynamics of microbial composition and function along with site-specificity while also assessing cross-site microbial interactions. We focus exclusively on females to address a critical knowledge gap to provide a foundation from which future research and interventions can be tailored to women's health. This review discusses the underlying mechanisms driving microbial shifts and their impact on host health, highlighting critical gaps in our current knowledge. The integration of findings from multi-site microbiome research, highlights the potential to inform targeted, preventative, and therapeutic strategies that utilise the inherent dynamic nature of the microbiome to improve health outcomes across the female lifespan.