In newborns, the level of vitamin E in blood is very low as compared to that of placental intervillous blood and maternal blood. In our attempt to investigate the role of placenta in the transfer of vitamin E from the maternal to the newborn circulation, we have discovered that vitamin E is able to enter placental blood but is not being efficiently transferred from the placental to the newborn circulation. It appears from our preliminary study that the most limiting factor in the transfer of vitamin E from the placental to the newborn circulation is the transient deficiency of prebeta lipoprotein in the newborn blood at birth. A transient lipoprotein deficiency is implicated as a cause of low levels of vitamin E in the newborn.