Successful Full-Term Pregnancy in Clinically Diagnosed Congenital Thrombotic Thrombocytopenic Purpura: A Case Report and Literature Review.

Introduction: Thrombotic thrombocytopenic purpura (TTP) is a rare, life-threatening thrombotic microangiopathy resulting from severe ADAMTS13deficiency. Congenital TTP (cTTP, Upshaw-Schulman syndrome) arises from biallelic mutations in the ADAMTS13 gene, leading to lifelong enzyme deficiency, often manifesting in childhood and requiring chronic plasma replacement. Pregnancy physiologically decreases ADAMTS13 activity, predisposing affected women to relapses and adverse outcomes if untreated. Case Presentation: We report a case of a 32-year-old Iranian woman with childhood-onset cTTP managed with long-term fresh frozen plasma (FFP) prophylaxis. After two early miscarriages, her regimen was intensified to FFP every 10 days. During her third pregnancy, ADAMTS13 monitoring was limited, so surrogate markers (platelet count and lactate dehydrogenase) guided therapy. In the third trimester, when ADAMTS13 reached the lower normal limit, FFP was increased to weekly. She delivered a healthy male infant (3200 g, Apgar 8/10) at 37 weeks + 4 days via cesarean section, complicated only by diet-controlled gestational diabetes. Discussion: This case highlights that individualized FFP prophylaxis can enable successful full-term pregnancy in cTTP even in resource-limited settings lacking ADAMTS13 testing. Reliance on clinical and hemolysis markers offers a practical alternative for monitoring. Prophylactic plasma replacement remains essential to prevent relapses and optimize maternal-fetal outcomes in cTTP pregnancies. Trial Registration: The authors have confirmed clinical trial registration is not needed for this submission.