Estimation of the risk of thrombocytopenia in the offspring of pregnant women with presumed immune thrombocytopenic purpura

Abstract

Abstract Background and Methods. The optimal management of immune thrombocytopenic purpura during pregnancy remains controversial because the risk of severe neonatal thrombocytopenia remains uncertain. We studied the outcome of the index pregnancy in 162 women with a presumptive diagnosis of immune thrombocytopenic purpura to determine the frequency of neonatal thrombocytopenia and to determine whether neonatal risk could be predicted antenatally by history or platelet-antibody testing. Results. Two maternal characteristics were identified as predicting a low risk of severe neonatal thrombocytopenia: the absence of a history of immune thrombocytopenic purpura before pregnancy, and the absence of circulating platelet antibodies in the women who did have a history of the condition. Eighteen of 88 neonates (20 percent; 95 percent confidence interval, 13 to 30 percent) born to women with a history of immune thrombocytopenic purpura had severe thrombocytopenia (platelet count <50×109 per liter at birth), as co...