Neonatal alloimmune thrombocytopenia: spontaneous in utero intracranial hemorrhage.

Neonatal alloimmune thrombocytopenia is an uncommon but important cause of thrombocytopenia in infants. Because of the severity of the thrombocytopenia, some of these infants will have intracranial hemorrhage with resultant long-term disability. Obstetricians and neonatologists have recommended delivery by caesarean section and the rapid institution of appropriate treatment for the infant; however, it is theoretically possible that a hemorrhagic event could precede the delivery and consequently not be prevented by these perinatal interventions. In this report we describe a neonate in whom the diagnosis of alloimmune neonatal thrombocytopenia was suspected because of antenatal ultrasound evidence of intracerebral hemorrhage. This case demonstrates the importance of antenatal fetal assessment and indicates the need for the development of therapeutic strategies to maintain fetal hemostasis.