The Effects Of Different Cord Clamping Time In Preterm Infants By Vaginal Delivery

Objective:We compared the effects of immediate (ICC) and delayed (DCC) cord clamping in vaginal birth preterm infants, and estimated the clinical outcomes and risks in different time of delayed cord clamping, in order to provide evidence to the optimal time of premature cord clamping.Methods:Neonates were excluded from delayed cord clamping if they needed immediate major resuscitation. A randomized controlled trial recruited120infants between28and35weeks. Immediately before delivery, mothers were randomized to4groups:A (immediate,<10s)、B(delay30s)、C(delay60s)、D(delay120S). Then examine the level of Hb and HCT at age of24hours and1week, compare the peak TCB and rates of anemia, hyperbilirubinemia and intraventricular hemorrhage (IVH), etc. Results:Primary outcomes were higher haematocrit(HCT) and haemoglobin(Hb) levels at24hours and1week after birth in all DCC groups than the ICC group. The120s DCC group has higher Hb and HCT level than the30s and60s groups at1week of age. DCC groups have significantly lower incidence of anaemia and fewer blood transfusions. There were no differences in the incidence of hyperbilirubinemia, phototherapy, peak TCB and IVH.Conclusion:Delayed cord clamping (30s-120s) in vaginal birth preterm infants with the infant held at the level of introitus is an effective, physiological and convenient practice, did increase the HCT and Hb levels, and is associated with lower incidence of anaemia and fewer blood transfusions. Considering the further resuscitation,30s delayed cord clamping is optimal for preterm infants.