[Letter BMJ 2002] Cerebral Palsy and Cord Blood Gases by Dr. George Malcolm Morley - A Letter to the Editor of the British Medical Journal.
Birth asphyxia (lack of oxygen) causes newborn brain damage.
Before birth, the placenta supplies the brain with oxygen.
After birth, the lungs supply the brain with oxygen.
After the delivery of the child, and before delivery of the placenta, the oxygen supply changes from the placenta to the lungs.
During normal changeover, placental oxygenation continues until pulmonary oxygenation is established.
During normal changeover, the brain is not deprived of oxygen.
During normal changeover, placental blood is transfused into the child, increasing its blood volume.
The increased blood volume flows through the lungs augmented by ventilation to establish pulmonary oxygenation.
After pulmonary oxygenation is established, placental oxygenation ceases - the cord vessels close; the brain's oxygen supply is not interrupted.
The child's innate reflexes control all the above mechanisms and functions.
Those reflexes have been developed over millions of years for optimal survival of the newborn.
Placental oxygenation is arrested and the brain is deprived of oxygen until the lungs function.
Placental transfusion is arrested and the child is hypovolemic.
Blood flow through the lungs and other organs is not optimal and pulmonary oxygenation is not optimal.
The child’s life support systems are not optimal for survival or for optimum health.
Depending on the degree of asphyxia and the length of time of asphyxia produced by cord clamping, the child will have varying degrees of brain damage that range from no damage through degrees of neurological impairment to brain death. Natural (normal) cord closure prevents birth asphyxia and prevents brain damage. Articles on this website explain how modern obstetrical and neonatal care is causing newborn brain damage and how that care can be corrected; they provides references to support the explanation.