Table 2.

Summary of the mechanism of microbiomes changes and PCOS.

Mechanism	Microbiomes changes
Inducing high level of androgen	Decreased alpha diversity
Inducing obesity	Decreased alpha diversity
Changing immune homeostasis	Disrupted Lactobacillus
Inducing insulin resistance	Increased Prevotella copri
Inducing insulin resistance	Increased Bacteroides vulgatus
Regulating the gut–brain axis	Unbalanced gut microbiota community
Inducing chronic inflammatory state	Unbalanced gut microbiota community
Disrupting intestinal integrity	Unbalanced gut microbiota community promoting release of pro-inflammatory factors