Pregnancy-Associated Thrombotic Thrombocytopenic Purpura: Diagnostic Pitfalls, Therapeutic Strategies, and Emerging Paradigms

<b>Background</b>: Thrombotic thrombocytopenic purpura (TTP) is a rare but life-threatening thrombotic microangiopathy (TMA) caused by severe deficiency of the von Willebrand factor-cleaving protease ADAMTS13. Pregnancy is a recognized trigger for both immune-mediated and congenital TTP and is associated with increased maternal and fetal morbidity. Clinical overlap with other pregnancy-associated TMAs, including preeclampsia and Hemolysis, Elevated Liver enzymes, and Low Platelet count (HELLP) syndrome, often delays diagnosis. This review synthesizes current evidence on pathophysiology, diagnostic uncertainty, and gestation-specific management of pregnancy-associated TTP, highlighting differences between immune-mediated and congenital disease. <b>Methods</b>: This is a narrative review. We performed a targeted literature search of PubMed/MEDLINE (from inception to December 2025) to identify English-language publications. The study types included were case reports/series, observational studies, large database studies, randomized trials, reviews, and relevant guidelines addressing TMA in pregnancy, with emphasis on immune-mediated and congenital TTP. Search terms included "pregnancy", "thrombotic thrombocytopenic purpura", "hereditary TTP", "acquired TTP", "ADAMTS13," "thrombotic microangiopathy," "HELLP," "postpartum", and "complement-mediated TMA" alone or in combination. The search was supplemented by manual screening of reference lists and key guidelines. Articles were selected based on relevance to diagnosis and management of pregnancy-associated TTP. Conference abstracts and non-peer-reviewed sources were not routinely included and were considered only when peer-reviewed evidence was limited. <b>Results</b>: Pregnancy-associated TTP remains a major diagnostic challenge due to overlapping clinical and laboratory features with other obstetric thrombotic microangiopathies. Distinguishing immune-mediated from congenital TTP is essential, as management and prognosis differ substantially. Prompt recognition and early initiation of therapeutic plasma exchange, immunosuppression, or prophylactic plasma therapy markedly improve maternal outcomes. Rapid ADAMTS13 testing, structured risk stratification, and multidisciplinary care are central to optimal management. Fetal outcomes are closely linked to gestational age at onset and timeliness of therapy. <b>Conclusions</b>: Early differentiation of TTP from other pregnancy-associated TMAs is critical for maternal and fetal survival. Advances in rapid ADAMTS13 diagnostics and emerging targeted therapies, including caplacizumab and recombinant ADAMTS13, offer opportunities to improve precision management and outcomes in future pregnancies.