New insights into neonatal hemostasis

Hemostasis is a dynamic process that starts in utero. Neonates, especially those who are born preterm, are at high risk of bleeding. The perinatal period is also associated with increased thrombosis risk as compared to older children. The coagulation system evolves with age, and the decreased levels of coagulation factors along with hypo-reactive platelets are counterbalanced by the increased activity of von Willebrand factor, high hematocrit and MCV as well as low levels of coagulation inhibitors that promote hemostasis. This review will address the concept and manifestations of developmental hemostasis with respect to the pathogenesis of severe bleeding or thrombosis in neonates. A special focus will be shared regarding intracerebral hemorrhages and perinatal arterial ischemic stroke. Hemostatic challenges associated with pathogenesis, diagnosis and treatment will be discussed.