A substantial increase in the RBC count in the neonates
compared with that in adults is the reason glucose is metabolized
very rapidly in neonates.2 Increased arterial oxygen
content within a few days of birth leads to an increase in
hemoglobin levels owing to the destruction of the RBCs.
Serum bilirubin levels then increase, because the immature
liver lacks enzymes to convert bilirubin to the water-soluble
bilirubin diglucuronide.2 The total number of neutrophils are
at a maximum for 1 to 2 days after birth. In the neonate, the
monocyte count is increased for up to 2 weeks after birth,
while the eosinophil count stays elevated for up to 1 week
after birth.5,6 The lymphocyte count is increased markedly at
birth and remains elevated in children up to 4 years of age.6
In contrast, the basophil count is elevated only transiently for
up to 1 day after birth. A substantial decrease in serum uric
acid levels is noted between days 1 and 6 after birth.2