ABSTRACT
DEFINITION Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is fetal/neonatal thrombocytopenia due to platelet destruction from maternal antibodies against fetal human platelet antigens (HPAs) inherited from the father. It is also called neonatal alloimmune thrombocytopenia (NAIT), alloimmune thrombocytopenia (AIT), or fetal maternal alloimmune thrombocytopenia (FMAIT).
