Here in the US, practitioners usually bring the baby out of the water within the first ten seconds after birth. There is no physiological reason to leave the baby under the water for any length of time. There are several water birth videos that depict leaving the baby under the water for several moments after birth and the babies are just fine. Physiologically, the placenta is supporting the baby with oxygen during this time though it can never be predicted when the placenta will begin to separate causing the flow of oxygen to baby to stop. The umbilical cord pulsating is not a guarantee that the baby is receiving enough oxygen. The safe approach is to remove the baby, without hurrying, and gently place him into his mother’s arms.