Misdiagnosis of a normal fetal platelet count after coagulation of intrapartum scalp samples in autoimmune thrombocytopenic purpura.

Intrapartum fetal scalp sampling for platelet counts in maternal autoimmune thrombocytopenia has been advocated for determining route of delivery. We report a case in which two coagulated scalp samples were believed to indicate a normal fetal platelet count. As a result, vaginal delivery of a severely thrombocytopenic fetus was allowed.