Pregnancy-associated acquired haemophilia A: results from the European Acquired Haemophilia (EACH2) registry

Objective The European Acquired Haemophilia registry (EACH2) collected data on the demographics, diagnosis, underlying disorders, bleeding characteristics, treatment, and outcome of women with acquired haemophilia A (AHA), a rare and often severe bleeding disorder caused by autoantibodies directed against coagulation factor VIII. Design Prospective, multi-centre, large-scale, pan-European registry. Setting A total of 117 haemophilia centres in 13 European countries. Population Pregnancy-associated AHA. Methods Data were reported using a web-based electronic case report form. Diagnosis was based on the presence of a prolonged activated partial thromboplastin time, reduced coagulation Factor VIII level and positive inhibitor assay. Main outcome measures Presenting characteristics, time to diagnosis, haemostatic treatment and outcome, immunosuppressive treatment and outcome. Results The EACH2 registry (n = 501) documented 42 (8.4%) cases of AHA associated with the peripartum period, a median Factor VIII level at diagnosis of 2.5 (range 0-25) IU/dl and inhibitor titre of 7.8 (range 0.7-348) BU/ml. Antepartum inhibitors were evident in eight women. Time to diagnosis of AHA after delivery was 89 (range 21-120) days. First-line haemostatic treatment was successful in 20/23 (87%) women treated. Bleeding episodes resolved in 17/18 (94%) women treated with a bypassing agent and 29/39 (74%) women achieved complete remission with first-line immunosuppressive treatment. Two babies experienced postnatal bleeding, suggesting transplacental transfer of the antibody. All women were alive at last follow-up. Conclusions Although rare, pregnancy-associated AHA may cause severe bleeding-related morbidity. Once diagnosed, women respond well to haemostatic treatment with bypassing agents and immunosuppression. Awareness of peripartum AHA requires improvement to facilitate rapid and appropriate management.