TY - CHAP M1 - Book, Section TI - Polycythemia A1 - Lo, Clara A1 - Wong, Wendy A2 - Stevenson, David K. A2 - Cohen, Ronald S. A2 - Sunshine, Philip PY - 2015 T2 - Neonatology: Clinical Practice and Procedures AB - The normal hematocrit of a healthy term infant ranges from 45% to 61%. This relatively high red cell mass is an adaptive response to the hypoxic intrauterine environment. Neonatal polycythemia, an abnormal elevation of red cell mass, is most often defined in textbooks as a venous hematocrit of 65% or more. It occurs in 1.5%–4% of healthy live births.1 Passive erythrocyte transfusion and increased fetal red cell production are 2 major causes for neonatal polycythemia. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/04/19 UR - accesspediatrics.mhmedical.com/content.aspx?aid=1109798729 ER -