Problem: To study the production, interrelationships and determinants of maternal and neonatal cytokines (IL-4 and IFN-gamma) in whole blood cultures during labor, after vaginal delivery and at 3 months after delivery.
Major results: The concentrations of maternal IFN-gamma and IL-4 in peripheral blood were down-regulated at delivery compared with values 3 months postpartum. The concentrations of neonatal IFN-gamma and IL-4 were down-regulated at birth and were still at a low level 3 months later. The concentrations of IFN-gamma in maternal and umbilical cord blood samples correlated at delivery (r=0.43; P<0.03). Maternal IL-4 concentrations correlated immediately after delivery and 3 months later (r=0.46; P<0.02) as did those of IFN-gamma (r=0.57; P<0.002). Neonates who were delivered at less than 40 weeks of gestation had higher IFN-gamma concentrations 3 months after birth than those who were delivered after a longer duration of gestation (341 vs. 157 pg/ml; P<0.01).
Conclusions: Broad immune activation, reflected in increased production of IL-4 and IFN-gamma, can be detected in women during the postpartum period. Labor-related factors had little effect on ranking of mothers in terms of their IL-4 or IFN-gamma levels, since maternal production of these cytokines correlated immediately after delivery and 3 months later. In neonates, the production of IFN-gamma 3 months after birth was dependent on gestational age at delivery.