The umbilical cord stops pulsing around 5-20 minutes after birth at that time the vessels are no longer open. The majority of homebirth midwives wait until the cord stops pulsating for maximum newborn blood perfusion. Late cord clamping has been proven to be physiologically more beneficial for then newborn. Newborns have a higher hematocrit and hemoglobin levels, blood pressure, and blood volume, with better cardiopulmonary adaptation and fewer days of oxygen and ventilation and fewer transfusions needed. Physiological studies have shown that there is a transfer from the placenta of about 80 ml of blood at 1 minute after birth, reaching about 100 ml at 3 minutes after birth which is equivalent to 30 to 35 mg of iron. Even babies at 2 months have more iron.
