CCL2 and preterm premature rupture of the membranes: Based on the occurrence of APO and the presence or absence of placental infection (PI), this study seeks to establish a possible relationship between the presence of PI by P. gingivalis and urogenital microorganisms (UGM) and the pattern of cytokine expression in the placenta (IFN-γ, IL-12p70, IL-17A, IL-17F, IL-23, IL-21, IL-10, IL-15, granzyme B, MCP-1, TNF-α, IL-1β, and IL-6) which may be related to the occurrence of APOs (e.g., LBW, PPROM, and PTB) and other clinical signs related to CA.