Abstract: Controversy has long existed about the optimal time to clamp and cut the umbilical cord for full-term and preterm infants. Policies for timing of cord clamping vary in different countries, with immediate cord clamping generally carried out in the first 15 seconds after birth, whereas delayed cord clamping usually involves clamping more than 30 seconds after the birth or when cord pulsation has ceased. Delayed cord clamping can increase the placental transfusion volume to infants, short term benefits associated with delayed cord clamping include increased hemoglobin level, prevention of intraventricular hemorrhage and late onset neonatal sepsis, without increasing the incidence of postpartum hemorrhage, long term benefits include increased iron storage and prevention of anemia in infancy.

Key words: Umbilical cord, Ligation, Placenta, Infant，premature