Selected cytokines, associated with Th1 and Th2 immune response and inflammation, were studied in order to evaluate the relation between their release into maternal and neonatal circulation, during labour, and after birth, in comparison with those in adults. Cytokine concentrations were determined by very sensitive immunoassays, in maternal serum (MS), umbilical cord (UC), neonatal serum, the 1st (1N) and 5th (5N) day postpartum and in adult controls. Both IL-2 and IL-4 cytokine concentrations in UC were markedly elevated, compared to adult and MS ones. IL-2 decreased significantly in 5N, while IL-4 remained unchanged. IFN-γ UC values were significantly lower than those in adults and MS, increasing significantly in 5N. Neonatal serum sIL-2R and sIL-4R were markedly higher than those in adults and MS. IL-1β, IL-6, sIL-6R, sTNFRI and sTNFRII concentrations in MS and all with TNF-α in neonatal serum were significantly higher than in adults. IFN-γ, IL-1β, IL-6, TNF-α, IL-2R, IL-4R concentrations in MS, 1N and 5N were dependent on the mode of delivery. The results of this comparative study are indicative for a meaningful role for the studied cytokines and their receptors in: i) the development of neonatal immune system, ii) the regulation of immune response during labour and early life, and iii) the initiation of the processes of labour.