Integrated microbiome and metabolomic analysis reveals associations between vaginal microbiota composition and psychological profiles

Abstract

The vaginal microbiota plays a key role in women’s health and is increasingly linked to psychobiological processes, although underlying mechanisms remain poorly understood. This study investigated the relationship between vaginal community state types (CSTs), psychological dimensions, and vaginal metabolites in 105 reproductive-aged women. Vaginal microbiota composition was characterised through 16 S rRNA gene sequencing and classified into CSTs; metabolomic profiling was performed using NMR spectroscopy. Participants completed validated questionnaires assessing trait anxiety, emotion regulation, behavioural inhibition/activation, depressive symptoms, perceived stress, and somatisation. Women with polymicrobial CST IV profiles showed significantly lower Behavioural Activation System (BAS)-Reward Responsiveness and BAS-Drive scores, whereas those with Lactobacillus iners -dominated CST III exhibited lower Behavioural Inhibition System (BIS) scores. Limited direct correlations between bacterial taxa and psychological variables emerged, but psychological dimensions strongly correlated with specific vaginal metabolites. Exploratory mediation analyses indicated that aminobutyrate and valine partially or fully mediated the associations between CST IV and BAS dimensions, while phenylalanine partially mediated the relationship between CST IV and BIS inhibition. These findings suggest that the vaginal metabolome may represent a functional interface linking microbial community structure and psychological functioning, supporting a biopsychosocial perspective of vaginal health and the importance of integrating microbiome, metabolomic, and psychological assessments in women’s health research.

The authors' abstract, as published at the source. Scientific Reports, 2026 · DOI ↗