Fetal thrombocytopenia : preventive strategies.

Abstract

Intracranial haemorrhage (ICH) among term neonates is associated with neonatal death or lifelong disability. Between all the proposed aetiological mechanisms, including impairments in coagulation, hypoxic-ischemic injury and birth related trauma, thrombocytopenia seems to be the most important predictor of ICH among term neonates and is also associated with the most severe forms of haemorrhage. Neonatal thrombocytopenia is defined as a platelet count < 150 x109/L. The incidence of thrombocytopenia (< 150 x 109/L) in all newborns is 1-4%. However, due to absence of clinical signs, mild or moderate thrombocytopenia is often not noted. Symptoms that might occur are petechiae, haematomas, gastro-intestinal bleedings and intracranial haemorrhages. Especially neonates with severe thrombocytopenia (<50 x109/L) are at risk for bleeding problems. Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is the most common cause of thrombocytopenia, especially in otherwise healthy term newborns. The aim of the studies described in this thesis was to contribute to improve the outcome of pregnancies complicated by fetal thrombocytopenia, caused by alloimmune thrombocytopenia, red cell alloimmunisation (Rhesus D and Kell) and Parvovirus B19 infection.