Different immunologic parameters were measured in cord blood to test their usefulness in the early diagnosis of early onset sepsis. Cord blood levels of circulating intercellular adhesion molecule-1 (cICAM-1), interleukin-6 (IL-6) and interleukin-8 (IL-8) were significantly elevated in septic compared to nonseptic neonates. No significant difference between either population was seen for cord blood C3a and elastase-alpha 1-proteinase inhibitor complex (E alpha 1 PI). Measured concentrations of cICAM-1, IL-6 and IL-8 in fetal and maternal blood did not correlate, indicating that the neonate's response to sepsis is clearly different from the mother. Our data suggest that cord blood measurements of cICAM-1, IL-6 and IL-8 might be useful in identifying neonates with early-onset sepsis.