Provided that the cord is not clamped for the first 5 minutes after birth, and kept level with the newborn, it allows baby to receive many maternal antibodies, critical stem cells, hormones, and vitamin K and provides the neonate with one-third to one-half of its entire blood volume.
Loss of this volume of blood through harvesting for blood banking can be the equivalent of subjecting an infant to a massive hemorrhage. This cord blood is a rich source of primitive, undifferentiated stem cells (i.e. CD34-positive and CD38-negative) which assist in neonatal adaptation. A cord blood bank is in the business of cord blood harvesting, and is NASDAQ listed. These companies promote very early cord clamping and cutting, to freeze for long-term cryo-storage at a cord blood bank should the child ever require the cord blood stem cells for rare diseases (for example, to replace bone marrow destroyed when treating leukemia). This practice is controversial: the RCOG (Royal College of Obstetricians and Gynaecologists, Great Britain) in its 2006 opinion states, "There is still insufficient evidence to recommend directed commercial cord blood collection and stem-cell storage in low-risk families." Child health advocates criticize the aggressive marketing campaigns of blood banks to pregnant parents-to-be as misleading, and assert that early cord blood withdrawal may actually increase the likelihood of childhood disease.
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