Gut microbiota in women with polycystic ovary syndrome: an individual based analysis of publicly available data.

Background: Polycystic ovary syndrome (PCOS) represents a prevalent endocrine disorder affecting numerous females worldwide. Dysbiosis of gut microbiota has been linked to the occurrence of PCOS; however, research into the characteristics of gut microbiota in PCOS patients, especially those from different regions and with different testosterone level, remains limited. Additionally, it is still unclear whether gut microbiota helps to distinguish different PCOS subtypes.

Methods: We searched four electronic databases (PubMed, Web of Science, Cochrane Library, and ClinicalTrials.gov) from Jan 1, 2010 to May 1, 2024. This combined analysis included studies providing the raw data of gut microbiota in PCOS patients. We reanalyzed the characteristics of gut microbiota in PCOS patients from different regions and with different testosterone level.

Findings: Fourteen publications satisfying the inclusion criteria were included in the combined analysis. Based on data from 948 individuals, we found alpha-diversity was not significantly different between PCOS and healthy control (HC) groups. However, gut microbiota composition was distinct in PCOS patients compared with healthy individuals. Specifically, Fusobacterium, Ruminococcus_gnavus_group, and Escherichia-Shigella increased, while Dysosmobacter, Schaedlerella, Merdimonas, Clostridiisalibacter, Flintibacter et al. decreased in PCOS women. Regionally, Alistipes was enriched in primarily European patients, while Blautia and Roseburia were more abundant in Chinese patients. Subtype analysis revealed that the gut microbiota of PCOS patients with higher testosterone level (PCOS-HT) differed significantly from those with lower testosterone level (PCOS-LT). Prevotella, Blautia, Dialister, Ruminococcus_torques_group and UCG-002 were enhanced in PCOS-HT patients, while Alistipes, Dysosmobacter, Phocaeicola and Faecalibacterium were diminished. Importantly, a set of eight genera effectively differentiated PCOS-HT patients from PCOS-LT patients with an AUC of 0.95.

Interpretation: This systematic anatomization of gut microbiota revealed the microbial characteristics of PCOS patients, particularly those with different testosterone level, thus laying the foundations for further research into pathogenesis of PCOS, and the development of effective diagnostic, treatment, and intervention strategies.

Funding: This work was supported by the National Natural Science Foundation of China (No. 81973217, 82260304), the Hainan Province Clinical Medical Center (QWYH202175), and the Specific Research Fund of The Innovation Platform for Academicians of Hainan Province (YSPTZX202311).