The immaturity of organs and enzyme systems contributes greatly to the difficulty of neonatal adjustment of premature infants. Their special needs for minerals and vitamins have been discussed by Levine and Gordon.1 The degree to which absorption, storage and requirement of vitamin A are influenced by prematurity is a subject on which there is little information.
Accurate methods for the determination of the vitamin A content of plasma are now available for clinical use, but because of the wide range of values found in normal persons the results are difficult to interpret. Lewis and his associates have showna relation between plasma levels, intake and hepatic stores of vitamin A in animals.2 This relationship has also been suggested for human infants,3 though it may be altered in the neonatal period because of immaturity of the mechanism for mobilization of the vitamin from body stores.4
The present investigation