Normal levels of Interleukin 6 (IL-6) and tumor necrosis factor (TNF) in healthy term and preterm infants have not been established. Objective of this study was to determine differences in the level of IL-6 and TNF in the cord plasma of healthy term and preterm infants. Cord blood samples were collected within 15 minutes from birth and centrifuged at 5000 rpm for 15 minutes. Serum was stored in -70°C until processing. IL-6 and TNF determinations were measured using the quantitative enzyme immunoassay technique (Quantikine ELISA kits, R&D).

Results: There were a total of 22 infants, 14 (64%) terms and 8(36%) preterms. Among the term infants the mean gestational age was 39.6±0.7 weeks and the mean birthweight was 3152±337g. Seven(50%) were males and mode of delivery was vaginal in 6(75%). Detectable levels of IL-6 (range 14-28 pg/ml) were measured among 4/14 (29%) of term infants. None of the preterms had detectable levels of IL-6. There was no significant difference in the mean TNF level between term and preterms (2.53±1.36 vs. 3.47±1.08 pg/ml, p=0.120).

Conclusion: We conclude that IL-6 is not detectable in the cord plasma of the majority of healthy term and preterm infants. Low levels of TNF are detectable in the cord plasma of healthy term and preterm infants.