CXCL8 and atrial fibrillation: The multivariable Firth’s logistic regression analysis revealed that the elevated AF levels of S100 A8/A9 and TIMP-1, but not APRIL, IL-8, and MIP-1α, were significantly associated with SPTD at <34 weeks of gestation after cerclage, when adjusted for cervical dilatation and corticosteroid administration (Table 4).