Reprinted from:
bmj.com/cgi/eletters/323/7326/1389#18099
by G. M. Morley, MB, ChB (Ed.), FACOG
From:
http://www.bmj.com/cgi/eletters/323/7326/1389#18099
A recent study in the British Medical Journal adds more evidence to the association of infant anemia with neurological impairment [1]. However, the 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 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]
At normal birth, continuous brain oxygenation is supplied from the placenta until the lungs are oxygenating the brain, at which 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. Immediate cord clamping, as promoted by the American College of Obstetricians and Gynecologists[4] and as demanded by resuscitation neonatologists, produces immediate neonatal asphyxia until the lungs function; it also prevents placental transfusion, thus delaying adequate pulmonary perfusion and pulmonary respiration.[3][4]
If the consequent asphyxia is not reversed within six minutes, brain damage will occur and progress.
The immediately clamped newborn, deprived of up to 50% of its normal blood volume, is also doomed to develop infant 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 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. Anemia is NOT the primary cause of the neurological defect, but a coincidental effect of hypovolemia induced by immediate cord clamping.
The hypoxic, ischemic brain lesions will not improve with treatment of anemia.
In many "primitive" births, the mother or midwife severs the cord (without 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, the anemia must have developed gradually after birth and the language/motor defects and their subsequent improvement may indicate neurological impairment caused by anemia and reversible by correction of anemia.
Physiological cord closure (placental transfusion) produces a physiological blood volume optimal for survival, and a healthy, normal baby. It does not routinely cause pathological jaundice, hypervolmia, hyperviscosity, polycythemia or plethora; if it did, Man would be extinct.
Immediate cord clamping [5] is universally condemned in the literature.
It causes loss of placental oxygenation and lack of blood volume; the consequent hypoxic, ischemic encephalopathy may cause neonatal death[8] or spastic paralysis, or it may be so mild as to cause behavioral defects which only become apparent in grade school. The associated infant anemia[7] is only a reflection of how much of the infantīs 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, a website is currently being set up (www.cordclamping.com). The site should be operational within the next few weeks. If you would like to be notified by email when it is working, please send an email to camermer@yahoo.com.
References:
[1] Stoltzfus RJ, Kvalsvig JD, Chwaya HM, Montresor A, Albonico M, Tielsch JM, Savioli L, Pollitt E. Effects of iron supplementation and anthelmintic treatment on motor and language development of preschool children in Zanzibar: double blind, placebo controlled study. BMJ 2001;323:1389.
[2] Windle, WF "Brain Damage by Asphyxia at Birth". Scientific American 1969 Oct; 221(4):76-84.
[3] Morley GM. "Cord Closure: Can Hasty Clamping Injure the Newborn?" OBG MANAGEMENT July 1998, 29-36.
[4] Morley GM. Letters. OBSTETRICS & GYNECOLOGY, Vol 97. No.6 June 2001 1024-1026.
[5] ACOG; 1995 Umbilical Artery Blood Acid-Base Analysis. Educational Bulletin 216.
[6] Linderkamp O. Placental Transfusion: Determinants and Effects. Clin Perinatol. 1982 Oct;9 (3):559-92. 1982; 9: 559-592.
[7] Hurtado EK et al. Early childhood anemia and mild to moderate mental retardation. Am J Clin Nutr. 1999; 69(1): 115-119
[8] Peltonen T. Placental transfusion - Advantage and Disadvantage. Euro. Journal of Paediatrics, 1981; 137: 141-146.
[9]Erasmus Darwin, Zoonomia 1801: "Another thing that is very injurious to the child, is the tying and cutting of the navel-string too soon; which should always be left until the child has not only repeatedly breathed, but also until all pulsation in the cord ceases. As otherwise the child is much weaker than it ought to be, a part of the blood being left in the placenta, which ought to have been in the child."
Reprinted from:
bmj.com/cgi/eletters/323/7326/1389#18099