The evaluation of cord blood interleukin-1[Beta] levels in normal and caesarean deliveries

Objective: The aim of this prospective study was to establish the cord blood interleukin 1b (IL-1b) levels and asphyxia enzymes in term newborns and their relationship between delivery modes. We investigated whether cord blood level of IL-1b could be used as a reliable marker for detecting hypoxic stress and to determine the optimal cut-off level for IL-1b. Methods: The study was designed prospectively. Cord blood samples were obtained at the time of delivery from 75 noninfected full-term neonates for the purpose of measuring cord blood levels of IL-1b. Women were classified into three groups according to the mode of delivery (20 vaginal delivery, 29 urgent caesarean section (with foetal distress) and 26 elective caesarean section). All cases were followed-up by hospitalization. Umbilical cord sampling was carried out for IL-1b, umbilical artery gas parameters and other asphyxia enzymes at the time of delivery. Cord blood IL-1b was measured by enzyme-linked immunosorbent assay. The perinatal outcomes of the cases were recorded after birth. Demographic characteristics, neonatal outcomes and laboratory findings were compared in all the three groups. Results: IL-1b levels showed statistically significant difference between groups (p < 0.01). The relationship was found between IL-1b cord blood levels and the mode of delivery. IL-1b levels of urgent caesarean section group were significantly higher than elective caesarean section and normal delivery group (p:0.001 and p:0.001, respectively). Normal delivery levels were significantly higher than the elective caesarean group (p:0.001). Conclusion: Urgent section (foetal distress) and vaginal delivery (labor) were each associated with elevated IL-1b cord blood levels in noninfected full-term neonates, while only elective caesarean section was associated with decreased IL-1b levels. For the evaluation of newborns at high risk for perinatal hypoxic stress, cord blood IL-1b levels may lead the way. On the other hand, the mode of delivery may be associated with the effects on the immune system. Further investigations with larger patient groups are required to confirm our results.