Does umbilical cord blood-derived CD34+ cell concentration depend on the weight and sex of a full-term infant?

Umbilical cord blood has recently been considered as an alternative source of hematopoietic progenitor cells for clinical application. Patient survival in allogenic cord blood transplantation is critically dependent on the cord blood-derived total nucleated cell count and the total CD34 cell count/kg of the body weight. A number of factors such as maternal age, gestational age, newborn's sex and weight, umbilical cord length, and placental weight can influence the volume, amount of mononuclear cells, and the CD34 cell concentration. Cord blood was collected from normal vaginal and cesarean deliveries. It was immediately processed and assessed for the total nucleated cell count and CD34 cell concentration. Assessment of maternal and neonatal parameters such as gestational age, baby's birth weight, and sex was carried out with the CD34 cell concentration. The mean CD34 cell concentration was 0.21±0.24% for the group with <2500 g (low birth weight) birth weight of the baby (n=104). The mean CD34 cell concentration was 1.84±1.12% for the group with ≥2500 g (normal birth weight) birth weight of the baby (n=396). A strong positive correlation was found between birth weight of the baby with cord blood-derived CD34 cell concentration (*P<0.0001, r=0.81). A positive correlation was found between gestational age and cord blood-derived CD34 cell concentration (*P<0.0001, r=0.31). No significant correlation was found between the baby's sex with the CD34 cell concentration and the total nucleated cell count. This study concludes that the higher the birth weight of the baby, the better the yield of the CD34 cell concentration, and hence these should be the preferred samples for infusion.