Anemia in Preterm Infants
Philip Roth MD, PhD1
1 Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, NY
Editors: Henry M. Adam, MD.
During fetal life, hemoglobin concentration increases from a level of 9 g/dL at l0 weeks' to 14 to 15 g/dL at 22 to 24 weeks' gestation. By the middle of the third trimester, concentrations close to those observed at birth (16 to 17 g/dL) are reached, and little additional change occurs. As a result, cord hemoglobin concentrations in term and preterm newborns are very similar, with the possible exception of the most extremely preterm infants. Immediately after birth, the hemoglobin concentration begins to rise from the combined effects of placental transfusion and the postnatal readjustment of plasma volume. At approximately 8 to 12 hours of life, the hemoglobin plateaus at levels 1 to 2 g/dL above those observed at birth (about 18 g/dL).
