The relative importance of maternal iron deficiency as a predisposing factor in the development of hypochromic anemia (nutritional or iron deficiency anemia) in infants is difficult to evaluate. Several recent studies of iron metabolism provide pertinent evidence. The stores of iron in the developing fetus are derived entirely from the maternal supply of this element by the transfer of iron across the placental membranes. The iron content of fetuses of varying weights has been reinvestigated by Widdowson and Spray,1who found that the iron concentration in the fetus remains constant throughout intrauterine life. The concentration averages about 7.5 mg. per 100 gm. of fetal weight. The liver and spleen contain less than 19% of the total fetal iron. The quantitative importance of the transfer of iron to the fetus during the last trimester of pregnancy depends upon the greater absolute growth during this period. During the latter half of