Closure times measured by the platelet function analyzer PFA-100 are longer in neonatal blood compared to cord blood samples.

Background: Although neonatal platelets have been shown to be hyporesponsive to most agonists in vitro, several groups have reported shorter closure times (CT) in term cord blood samples than in children and adults. It is unknown whether this is also true for preterm neonates, or for neonates of any gestational age (GA) during the 1st week of life, since limited studies have evaluated neonatal blood samples.

Objectives: We designed this study to determine the effects of GA and postconceptional age on platelet function using the platelet function analyzer PFA-100.