Recent studies showed that the anti-inflammatory and immune mechanisms of PID were related to T cells, B cells, IG, cytokines (e.g., IL-6, TNF-α, and IL-1β), prostaglandin-endoperoxide synthase 2 (PTGS2), matrix metalloprotein-9 (MMP9), and TLRs signaling pathways [8, 10]. Here, MMP9 is linked to pelvic inflammatory disease.