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Note: For additional articles and studies concerning Cord Clamping, written by Dr. Morley and others, CLICK HERE.
Lost Causes and Side Effects: The Neurological Damage Caused by Immediate Cord Clamping is Irreversible
by G. M. Morley, MB, ChB (Ed.), FACOG
A recent study in the British Medical Journal adds more evidence to the association of infant anemia with neurological impairment [1]. However, the small improvement in language/motor disability with iron therapy in this study contrasts with other studies which show no resolution of grade-school neurological defects with iron therapy in infancy.
This difference may be explained by the fact that the study took place in Zanzibar, rather than in a Western nation, engaging in modern medical childbirth practices. This is due to the fact that there are differing causes of the anemia and, consequently, different primary causes of the neurological defects.
Neonatal asphyxia (hypoxia) for as short a time as six minutes causes permanent neurological damage - death of neurons. Loss of brain tissue has been demonstrated in asphyxiated newborn primates and correlated with memory dysfunction and spastic paralysis. [2]
During a "normal" birth (unclamped umbilical cord), continuous brain oxygenation is provided by the placenta until the infant's lungs are oxygenating the brain. At this time the cord vessels close reflexively. During this interval, the placental transfusion supplies additional blood volume for adequate perfusion of the pulmonary vessels and gaseous exchange.[3][4] This duplicate placental/pulmonary oxygenation precludes hypoxic brain damage and adequate blood volume prevents ischemic brain damage.
On the other hand, immediate cord clamping, as promoted by the American College of Obstetricians and Gynecologists (ACOG) [4] and as unnecessarily demanded by resuscitation neonatologists, produces immediate neonatal asphyxia until the lungs begin to function. It also prevents placental transfusion, thus delaying adequate pulmonary perfusion and pulmonary respiration.[3][4]
If the consequential asphyxia is not reversed within six minutes, brain damage will occur and progress, until the lungs begin to function.
The immediately clamped newborn, deprived of up to 50% of its normal blood volume, is also doomed to develop iron deficiency anemia.[6]
The child which is delivered without the use of a cord clamp receives a full placental transfusion with enough iron to prevent anemia for the first year of life;[6] newborn hemoglobin levels are high regardless of the iron status of the mother. Such a child would appear to be immune to neurological defects "caused" by anemia. Hurtado, et al, correlated the degree of grade school mental deficiency with the degree of infant anemia.[7]
Thus, neurological defects of hypoxic/ischemic origin share a common cause with infant anemia - premature clamping of the umbilical cord at birth. The anemia is NOT the primary cause of the neurological defect, but a coincidental effect of hypovolemia (inadequate blood volume) induced by immediate cord clamping.
Unfortunately, treatment of the resulting anemia will be of very limited benefit. The hypoxic/ischemic brain lesions will not improve with treatment of the iron deficiency anemia, nor with any other treatment.
In many "primitive" births, the mother or midwife severs the cord (without ever tying or clamping) after delivery of the placenta, long after the natural placental transfusion is complete. If this occurred, these neonates would not be anemic, hypovolemic or asphyxiated. Any subsequent anemia, such as that found in the study of anemic children in Zanzibar[1], must have developed gradually after birth. The language/motor defects seen and their subsequent improvement with iron supplementation may indicate neurological impairment caused by anemia and reversible by its correction.
Physiological cord closure (facilitating placental transfusion) produces a physiological blood volume optimal for survival, and a healthy, normal baby. Contrary to common misconceptions, it does not routinely cause pathological jaundice, hypervolemia (excess blood volume), hyperviscosity, polycythemia or plethora; if it did, the human race would be extinct.
Immediate cord clamping, as endorsed by ACOG[5] is a dangerous practice that is universally condemned in the literature. It causes loss of placental oxygenation and lack of blood volume; the consequent hypoxic, ischemic encephalopathy may cause obvious damage resulting in neonatal death[8] or spastic paralysis, or it may be so mild as to cause behavioral defects which only become apparent years later. The associated infant anemia[7] is only a reflection of how much of the infant's blood volume was left clamped in its placenta.[9]
The cord clamp is a very dangerous instrument.[3][4]
British Medical Journal web site, posted December 17, 2001
For more information on Cord Clamping, visit www.cordclamp.com.
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