Introduction

The human microbiome is defined as all the microorganisms whose activity forms ecological niches on and inside the human body, and which sustains a dynamic and interactive relationship with their human host, becoming crucial for their functioning and health1. The human microbiome is typically evaluated by body site, with the gut microbiome being the most studied. There has been interest in exploring the role of the vaginal microbiome on human health. The vaginal microbiome has been linked with reproductive health outcomes, including risk for sexually transmitted infections and adverse birth outcomes2,3.
Much of the research on the vaginal microbiome is observational and focuses on the absence or presence of bacteria within one genus‒Lactobacillus . The protective effect ofLactobacillus is largely attributed to its function of maintaining an acidic environment4,5. While Lactobacillus dominates the vaginal microbiome of most healthy individuals, there is a significant portion of healthy people whose vaginal microbiome is not dominated byLactobacillus , especially among Black and Hispanic individuals6.
The goal of this review is to discuss key endogenous and exogenous factors that clinical experts and research scientists should consider when evaluating the vaginal microbiome and its influence on health and disease. First, we will briefly overview the emergence of vaginal microbiome research as it is currently understood, and highlight some of the potential shortcomings and gaps in the science. Then, we will outline factors which are known to impact the vaginal microbiome and health outcomes which are important to consider in vaginal microbiome research, such as hygiene practices, diet, and stress. Finally, we will discuss future implications for clinical practice and research with a focus on how to move forward in this field and overcome the barriers discussed.