Successful management of pregnancy in women with a history of thrombotic thrombocytopaenic purpura.

Pregnancy is an initiating event for acute thrombotic thrombocytopaenic purpura (TTP). There is a high risk of relapse during pregnancy and of foetal morbidity. We describe five cases with successful maternal and foetal outcomes in patients with a history of TTP. Cases 1 and 2 presented with TTP in their first pregnancy and had second-trimester foetal losses. Case 3 had four TTP relapses and soon after achievement of clinical remission became pregnant. Case 4 presented with TTP and left-sided stroke in pregnancy. ADAMTS-13 activity was less than 5% at presentation in four patients and prior to therapy during pregnancy in cases 1-4. Case 5, who had a single acute episode of TTP and became pregnant 6 years later, had normal ADAMTS-13 activity throughout pregnancy. Only case 3 had evidence of an inhibitor on mixing studies. All five patients underwent close haematological and obstetric monitoring and continued low-dose aspirin throughout pregnancy. Patients 1-4 had regular plasma exchange and received low molecular weight heparin during pregnancy. Patient 4 also received rituximab during the third trimester with no observed maternal or neonatal toxicity. Live healthy infants were delivered in all five cases in the third trimester. These findings suggest that successful pregnancy outcome is achievable in patients with a history of TTP and that patients with severely reduced ADAMTS-13 activity at the onset of pregnancy, necessitates regular plasma exchange during pregnancy.