In two hundred neonates, white cell counts and peripheral blood smears were evaluated at birth, and after the 24th, 48th and 72nd hours of delivery to compare the differential counts of leukocytes with the values of other investigators. Parity between neutrophils and lymphocytes was observed on the third day, which was earlier than the time reported previously by other investigators. The total white cell counts were similar to those generally observed, but absolute total neutrophil counts, absolute total immature neutrophil counts and immature-to-total neutrophil ratio were found to be higher than those values previously reported in the literature. Environmental factors during delivery and in early postnatal life may play a role in the dynamics of leukocytes. These differentials should be taken into account when the diagnosis of early neonatal infections is considered.