Comparative Analysis of Midtrimester Amniotic Fluid Cytokine Levels to Predict Spontaneous Very Pre-term Birth in Patients with Cervical Insufficiency

Problem: Few studies have investigated the roles of cytokines and chemokines in women with cervical insufficiency, and those that have done so evaluated only a limited number of cytokines in amniotic fluid. Method of study: A retrospective cohort study enrolled 71 patients undergoing physical examination-indicated cerclage to determine whether expanded amniotic fluid cytokine levels predict spontaneous very pre-term birth (≤32 weeks of gestation) in patients with cervical insufficiency. Analysis of multiple cytokines and chemokines was performed with the multiplex immunoassay. Results: Sixty-seven amniotic fluid samples were available for analysis and assayed for 15 cytokines. Thirty-eight (56.7%) patients delivered pre-term. Of these, 26 (38.8%) were spontaneous very pre-term births. Most cytokine levels were significantly increased in the amniotic fluid from the study group when compared with those from controls. The levels of interleukin-1β (IL-1β), IL- 6, IL- 7, IL-15, IL-17α, tumour necrosis factor-α (TNF-α), MIP-1α, and MIP-1β were higher in patients with a very pre-term delivery than in those with a late pre-term delivery. IL-1β, IL-6, IL-7, IL-17α, TNF-α, and cervical dilation were independently associated with a very pre-term birth. Conclusion: Intra-amniotic inflammation may contribute to cervical insufficiency, and the severity of inflammation is associated with a very pre-term birth in women with cervical insufficiency.