IL22 and ovarian dysfunction: In a recent report, Qi et al. showed that serum IL‐22 level was also reduced in a mouse model of PCOS with gut microbiota modification, and administration of IL‐22 improved the PCOS phenotype, suggesting an important role of this anti‐inflammatory cytokine in gut microbiota‐induced insulin resistance and ovarian dysfunction in PCOS (Qi et al., 2019).