Platelet disorders in pregnancy are not uncommon. Most often, obstetricians are faced with a patient with undiagnosed
thrombocytopenia and have the responsibility of deciding if the condition is
ITP, gestational
thrombocytopenia, or a process related to
pre-eclampsia. Correct diagnosis is important because
ITP can be associated with fetal
thrombocytopenia, making route of delivery important. In alloimmune
thrombocytopenia, the mother develops
antibodies to a specific platelet
antigen present on the fetal platelet but absent on her own. Severe AIT can cause
intracranial hemorrhage and have disastrous consequences for the fetus and neonate. In preliminary studies antenatal intravenous
gamma globulin therapy has shown promise in preventing the development of
intracranial hemorrhage and ameliorating fetal
thrombocytopenia.
Essential thrombocythemia with a platelet count of greater than 600 x 10(9) platelet/L can occur in pregnancy;
therapy consists of antiplatelet aggregating agents such as
aspirin, and plateletpheresis. Platelet function disorders can be acquired or inherited. Acquired platelet dysfunction disorders are usually caused by drugs such as
aspirin or
indomethacin, or by a systemic disease. Hereditary disorders of platelet function can be diagnosed in utero, but cordocentesis may represent an unacceptably high risk. For prenatal diagnosis, other methods, such as chorionic villus sampling or amniocentesis, should be investigated as an alternative to the potentially high risk of cordocentesis.