Acquired thrombotic thrombocytopenic purpura (TTP) is a rare blood disorder where autoantibodies to the ADAMTS13 protease lead to small blood clots throughout the body.
TTP is commonly associated with immune disorders, certain medicines, and pregnancy. Little data, however, exists on pregnancy outcomes in patients with a history of acquired TTP. Jiang and colleagues followed 74 TTP patients over 17 years—10 of which were women who later became pregnant. Only two of the 10 women had recurrent TTP events during pregnancy, and 13 of 16 pregnancies resulted in normal babies (81%). However, three of the women had preeclampsia while pregnant (5/16 pregnancies, 31%), a frequency about 10 times higher than the normal US population. This is the largest study to date on pregnancy outcomes in TTP patients. Based on these data, the risk of reoccurring TTP during pregnancy is smaller than previously thought, but more data are needed to fully understand the risks and complications such as preeclampsia.
References
1. Battinelli EM. TTP and pregnancy. Blood 2014; 123(11): 1624-5.
2. Jiang Y, McIntosh JJ, Reese JA, et al. Pregnancy outcomes following recovery from acquired thrombotic thrombocytopenic purpura. Blood 2014; 123(11): 1674-80.
