Fig. 4

Changes in the relative abundance of microbes in the included studies. A Phylum and family level. B Genus level. C Species level. The red and blue grids indicate a statistically significant increase and decrease, respectively, in the taxa among patients with PCOS. The grey grids represent that the original studies did not report the results at the level of this taxa. In the total row, the numerical value in the grid indicates the count of studies that have reported a statistically significant alteration in the taxa. The red and blue grids represent the number of studies that have reported a statistically significant increase and decrease with PCOS, while the brown grids represent the equivalent number of studies that have reported a statistically significant increase as opposed to those reported a decrease. * represents the study with shotgun metagenomic sequencing. ↑↓ represents that there were increased and decreased species or OTU belonging to the taxa reported in studies. ? represents that the taxa were reported significantly changed without mentioning increasing or decreasing in PCOS. L2 to L7 represent phylum, class, order, family, genus, and species level respectively. OTUs, operational taxonomic units