Platelet activation during the early neonatal period

The first week of life is a time when hereditary or more frequently acquired factors lead to some important differences in the hemostatic mechanism of the newborn. It has been well known that ill neonates are prone to both hemorrhage and thrombosis. The aim of this study was to answer the question of whether there is a difference in platelet activation in healthy neonates during the first days of life that may contribute to both hemorrhage and thrombosis in the presence of additional pathologic insults. Platelet activation was determined with flow cytometry using monoclonal antibodies in 63 healthy children (29 neonates, 17 infants, and 17 older children). There was no significant difference in platelet activation among these three age groups (p > 0.05). In addition, platelet activation did not show any significant relationship to age, sex, mode of delivery, or blood bilirubin concentration (p > 0.05). It has been previously reported that platelet activation occurs at the time of birth. We could not find any evidence that healthy newborns during the first 3 days of life exhibit increased platelet activation. Further studies on platelet activation in ill neonates will help to clarify whether platelet activation plays a role in the pathogenesis of thrombotic and/or hemorrhagic disorders.