Vitamin C concentrations have been measured in the plasma of 200 mothers and their newborns as well as in amniotic fluid and breastmilk. Out of this group 19 mother-infant-pairs were taken as normal control group with no risk factors, complications or diseases during pregnancy or delivery or in the newborn infant. Vitamin C concentrations in plasma showed great variability. This is true for both the entire study group and the normal control group. A positive correlation was found between the vitamin C concentrations in maternal plasma at the time of admission to the obstetric unit and that in the second stage of labor immediately before delivery. Cord blood and newborn plasma vitamin C concentrations were nearly twice as high compared to maternal concentrations. They too correlate with the concentrations in the maternal plasma. A further correlation was found between maternal plasma and amniotic fluid at the time of delivery (ratio about 1:3). No more significant correlations of vitamin C concentrations have been found in the normal control group. Various diseases or risk factors in mother and/or child were shown to be associated with lower vitamin C concentrations. Vitamin C concentrations were considerably lower in all biological fluids in smokers and mothers with diabetes. Other statistical correlations will be shown and possible casualties will be discussed. In this study vitamin C concentrations in groups with abnormal states are documented only with small numbers of cases and are therefore considered as a basis for further more specific investigations.