The study presents a comparison of data concerning lipid metabolism and lipid oxidation (oxidative stress) in children at the time of their birth and 3 months later, as well as of their mothers at the time of delivery, compared to a control group of non-pregnant women of the same age. The data confirm that labour represents an oxidative stress for both mother and child; it is expressed as a significant increase of malondialdehyde concentration in mothers immediately after delivery in comparison with non-pregnant women (p<0.001). Its concentration in newborns was even higher than in their mothers (p<0.005). Concentration of antibodies against oxidized LDL (oxLDLAb) was comparable in mothers and newborns due to their transplacental transport. During the first three months of life these autoantibodies increased almost two-fold. The importance of this unique observation is discussed with respect to possible early atherogenesis.