Leaños-Miranda A, Nolasco-Leaños AG, Carrillo-Juárez RI, et al. - In view of the reported associating amniotic fluid (AF) interleukin-6 (IL-6) concentration with preterm delivery and perinatal morbidity and mortality in women with preterm labor and intact membranes, researchers sought to ascertain the clinical significance of this biomarker of intra-amniotic inflammation (IAI). A total of 452 consecutive women with preterm labor and intact membranes were assessed for AF IL-6 concentrations; these women were categorized into 3 groups: 302 without IAI (IL-6 of < 2.6 ng/mL), 64 with mild IAI (IL-6 of 2.6–11.2 ng/mL), and 86 with severe IAI (IL-6 of ≥ 11.3 ng/mL). A short pregnancy duration was reported from amniocentesis to delivery (median 3 days) in the severe IAI group relative to without IAI group (median 45 days); meanwhile, the mild IAI group had a latency that was intermediate to the severe and without IAI groups (median 9.5 days). Outcomes suggest AF IL-6 concentrations to be suitable marker for assessing the degree of IAI and their association with raised risk of adverse outcomes.