In pregnancies with PTL, both intra-amniotic infection and sterile inflammation were associated with elevated concentrations of IL-6 in the cervical fluid (intra-amniotic infection: median 587 pg/mL; sterile intra-amniotic inflammation, median: 590 pg/mL; without inflammation, median: 136 pg/mL) (107). Here, IL6 is linked to chorioamnionitis.