Reference intervals for cell counts of umbilical cord blood.

The umbilical cord blood is useful for assessing the health status in newborns. A limited number of studies evaluated the reference values of peripheral blood cell count and little information is available on the number of stem cells in umbilical cord blood. This study aimed to define reference intervals for hematological parameters in umbilical cord blood. 257 umbilical cord blood samples were obtained from apparently healthy infants with gestational age >37 weeks, uncomplicated pregnancy, birth weight >2500 g and umbilical arterial pH >7.0. The analysis was performed within 3 h from collection using the hematology analyzer Sysmex XN-1000. Reference values were derived with a non-parametric approach, by following the CLSI document EP28–A3c. A statistically significant difference between genders was observed for erythrocytes, hemoglobin, hematocrit and red blood cell distribution width, these parameters being significantly higher in males than in females. Results from this study may be seen as a useful guide for neonatologists to evaluate the newborn status and for hematologists to evaluate the quality of collected blood.