Median concentrations of 28 cytokines were significantly higher in preterm labor with sterile intra-amniotic inflammation compared to preterm labor without either intra-amniotic inflammation or proven intra-amniotic infection, with the highest fold changes being observed for Calgranulin C (log2 FC = 7.7), MIP-3α (log2 FC = 6.8), and IL-6 (log2 FC = 5.6). This evidence concerns the gene CCL20 and chorioamnionitis.