Immune complexes in cord serum: influence of sex, gestational age, and Rh- blood group--possible predictive value of high levels for early postnatal infections.

The levels of immune complexes (IC) were found to be lower in the cord sera of healthy full-term neonates than in the sera of blood donors. Among 26 neonates with high levels of IC, 21 (80%) were boys. IC levels were lower in neonates born before 37 weeks of gestation as they were in Rh- neonates. The main finding was that neonates with high levels of IC constitute a population at risk of developing an infection during the first week after birth: 48% as against only 9.5% with normal levels of IC, IC levels did not correlate with either the concentration of IgM, orosomucoid, bilirubin or the leucocyte count in cord blood nor were they clearly dependent on parity.