ADAMTS13 deficiency, an important cause of thrombocytopenia during pregnancy.

We present the case of a woman with congenital ADAMTS13 deficiency and discuss peripartum management of her fourth pregnancy. All four pregnancies were complicated by significant thrombocytopenia. Her first pregnancy ended with fetal demise ascribed to HELLP syndrome and placental abruption. During her second pregnancy, she was diagnosed with idiopathic thrombocytopenic purpura. Thrombotic thrombocytopenic purpura and congenital ADAMTS13 deficiency were diagnosed during the third pregnancy. She had recurrent thrombotic thrombocytopenic purpura during the fourth pregnancy and responded to treatment with fresh frozen plasma, with a successful outcome. The need for accurate diagnosis to ensure appropriate treatment is emphasized.