Elevation of interleukin-6 levels in cervical secretions as a predictor of preterm delivery

Abstract

Background. The objective of this study was to evaluate the predictive value of interleukin-6 (IL-6) in cervical secretions for preterm delivery before 34+0 gestational weeks in patients with preterm labor. Methods. In this prospective study, 31 patients were enrolled with preterm labor and intact membranes. Cervical swabs were taken on admission and the concentration of IL-6 was measured. The gestational age at the time of admission and delivery, as well as the time interval to delivery, were evaluated and compared with the concentration of IL-6 on admission. Results. Cervical IL-6 was significantly elevated in the preterm delivery group (< 34+0 gestational weeks, p < 0.05). Choosing 20 pg/ml as a cut-off concentration, cervical IL-6 had a sensitivity and negative predictive value of 100%, a specificity of 67% and a positive predictive value of 47%. Concerning the time interval to delivery, the sensitivity of IL-6 was 100% and the specificity 57% for delivery within 2 days and 100% and 64% for delivery within 7 days. Conclusions. Cervical IL-6 is a new, promising diagnostic tool to identify patients at high risk of preterm delivery.