In terms of inflammatory markers, increase of Treg cells prenatally (Krause et al., 2014), upregulation of IL-6 and high-sensitivity C-reactive protein (Hs-CRP) at delivery (Liu et al., 2016), high DNA methylation at FOXP3 Treg-cell-specific demethylated region (TSDR) prenatally (Sluiter et al., 2020), increase of the IL-8/IL-10 ratio during the third trimester (Corwin et al., 2015) are highly correlated with the occurrence of PPD. The gene discussed is IL6; the disease is progressive pseudorheumatoid arthropathy of childhood.