Association between oral microbial shifts and polycystic ovary syndrome: a systematic review

This systematic review aimed to assess the association between the oral microbiota and polycystic ovary syndrome (PCOS) and elucidate its potential clinical significance.

A comprehensive search of eight databases and other sources from inception to 13 January 2026, identified 10 eligible studies from 310 records, involving 334 PCOS patients and analyzed oral microbiota species and their clinical parameters correlation.

Oral microbiota alterations in PCOS women showed consistent and heterogeneous features, with Fusobacterium elevation as the most robust finding. However, the results for Porphyromonas gingivalis and Fusobacterium nucleatum varied with periodontal status. Specific oral microbial changes are correlated with core systemic features of PCOS, including hormonal dysregulation (e.g. elevated testosterone and luteinizing hormone) and metabolic disturbances (e.g. dyslipidemia and insulin resistance).

Oral microbiota alterations in PCOS are characterized by consistent Fusobacterium elevation and heterogeneous changes associated with systemic inflammation, metabolic‒endocrine disturbances and poor periodontal health. Despite the limited current evidence, the oral microbiota may serve as a novel entry point for PCOS management. Large, high‑quality prospective studies are warranted to clarify the causal relationship between the oral microbiota and PCOS, and to explore the feasibility of modulating the oral microbiota as a novel therapeutic strategy.