Behaviour of lab parameters and neonatal weight loss in relation to neonatal breathing movements and cord clamping time.

To date, delaying cord clamping two to three minutes after birth is considered effective for newborn well-being. This time does not consider the newborn's breathing movements, which may also condition neonate well-being. To investigate the behaviour of neonatal weight loss and of some umbilical vein lab parameters, in relation to timing of newborn breathing and cord clamping. Time from birth to cord clamping and time from birth to first cry of the newborn were collected in 87 full-term healthy women. First cry is a sign of effective breathing. Birth weight loss at the first, second, and third day from birth and lab parameters were assessed in relation to: time from birth to cord clamping, time from birth to first cry, and cord clamping before or after the first cry. Partial pressure of carbon dioxide (pCO2) decreased if cord clamping was performed after first cry and increased if first cry occurred after cord clamping, independently from the time elapsed from birth to first cry (p = 0.012). Calcium (Ca(2+)) concentration decreased if cord clamping was performed after the first cry and increased if first cry of the baby after birth was delayed (p = 0.021). Each second of delay from birth to cord clamping resulted in an increase in Cl- concentration (p <0.001). Each second of delay in cord clamping resulted in a reduction in the percentage of weight loss at the first day (p = 0.024), at the second day (p = 0.007), and at the third day (p = 0.028) after birth. Neonate breathing after birth should induce umbilical vein flow from placenta to lungs, conditioning the reduction of birth weight loss after birth and umbilical lab parameters modifications.