Effect of different timings of umbilical cord clamping on the level of CD34+ cells in full-term neonates

Sci Rep. 2023 Dec 21;13(1):22917. doi: 10.1038/s41598-023-50100-9.


Despite the fact that delayed cord clamping (DCC) is recommended by many international organizations, early cord clamping is still widely practiced worldwide. The overarching goal of the DCC practice is to maximize neonatal benefits as achieving higher hemoglobin levels and decreasing the incidence of anemia as well as avoiding the adverse consequences. The current study was conducted to identify the effect of of DCC on the number of CD34+ stem cells in cord blood of full term neonates after two different timings (30 and 60 s after birth). One hundred and three full-term (FT) newborn babies (gestational age 37-40 weeks) delivered by elective cesarean section were randomly assigned into 2 groups: Group 1: babies were subjected to DCC 30 s after birth (50 newborns). Group 2: babies were subjected to DCC 60 s after birth (53 newborns). Neonates in group 2 had significantly higher levels of hemoglobin, hematocrit, total nucleated cells and CD34+ cells compared to those in group 1. The practice of DCC 60 s after birth achieved better CD34+ stem cells transfer in FT neonates than clamping the cord after 30 s.

MeSH terms

  • Cesarean Section*
  • Female
  • Hemoglobins / analysis
  • Humans
  • Infant
  • Infant, Newborn
  • Pregnancy
  • Time Factors
  • Umbilical Cord / chemistry
  • Umbilical Cord Clamping*


  • Hemoglobins