Blood Formation in Infancy Part Iv*-the Early Anaemia of Prematurity

2 3 4 chromia of the red cells and a response to iron therapy, does not differ from the hypochromic anaemia common in other infants of over 6 months. It reflects the precarious iron balance during infancy, exaggerated by several factors which bear on the premature infant, such as its smaller initial iron stores, its more rapid growth, and its tendency to receive a purely milk diet for a prolonged period. These facts were established many years ago, Mackay (1935) having first clearly distinguished between the early and late phases of anaemia. The cause of the early anaemia of prematurity has, however, never been precisely understood. Three different mechanisms have been suggested. (1) That the anaemia is the result of an abnormally high rate of destruction of red cells. (2) That it is the result of the rapidity of body growth outstripping a normal erythropoietic capacity. (3) That it is the result of a functional immaturity of the bone