The present study compares the vitamin A plasma levels of pregnant women and their newborns (cord blood), in two different socioeconomic groups. One group was of low socioeconomic level and the other of high socioeconomic level. The results indicate a highly significant difference between the mothers of both groups, reflected in the levels in the newborns. Vitamin A concentration in the newborns was always lower than that found in the mothers. The data obtained allow the proposal of figures that could serve as a first approximation to establish criteria for determining the adequacy of retinol serum levels in cord blood.