Citizen-science map of the vaginal microbiome

Abstract

<title>Abstract</title> The vaginal microbiome is crucial for women’s health and reproduction, but its ecology and determinants in the general population are still unclear. This lack of a reference framework hampers much-needed innovations in diagnostics and therapeutics. Here, we remotely mapped the vaginal microbiome of 3,345 women in Western Europe via a citizen-science approach. More than 75% of the vaginal samples were dominated by Lactobacillus taxa, but not in discrete community state types. Compositional correlation network analysis validated with public data pointed at six main modules of interacting microbes: a <italic>Lactobacillus crispatus-, Lactobacillus iners-, Gardnerella-, Prevotella-, Anaerococcus-</italic>, and gut-derived module. In the first module, <italic>Limosilactobacillus </italic>taxa were functionally connected to <italic>L. crispatus</italic> and <italic>Lactobacillus jensenii</italic>. This module was positively associated with the luteal phase of the menstrual cycle and negatively with the number of vaginal complaints, while the <italic>Gardnerella</italic>-module was associated with discharge and increasing age. Contraceptives with oestrogen correlated with higher levels of the <italic>L. crispatus</italic>- and less of the <italic>Gardnerella</italic>-module, with the opposite found for a hormonal intrauterine device or having multiple partners. Mothers had lower relative abundance of the <italic>L. crispatus</italic>-module and more <italic>Bifidobacterium, Lactobacillus gasseri </italic>and <italic>Streptococcus</italic>. Other covariates such as BMI, menstrual pads and cups, smoking and dietary habits were also associated with the microbial constellation. These findings suggest that lifestyle interventions have potential to improve vaginal health when combined with dedicated therapies.