Acquired factor VIII inhibitors in pregnancy: data from the Italian Haemophilia Register relevant to clinical practice

Abstract
To review the clinical problems related to the inhibitor of factor VIII (FVIII) in pregnancy. Retrospective analysis. Haemophilia and haemotology centres. Patients registered and followed up at the centres. Data were collected from the Italian Haemophilia Register of acquired FVIII inhibitor. Twenty of 96 cases with FVIII inhibitor were identified postpartum. The time of appearance was 3-150 days postpartum. All but one of the cases were idiopathic; 11/20 patients required blood transfusions. In six patients, the inhibitor was identified because of surgical bleeding, four after hysterectomies carried out because of postpartum haemorrhage. A prolonged activated partial thromboplastin time was present in all women in whom the test was carried out. Nine women did not require treatment because the bleeding was mild; in 11 patients bleeding was promptly controlled by different therapeutic modalities. Immunosuppressive therapy was used to suppress the inhibitor. The majority of the patients who achieved complete remission received steroids; in 6/6 patients who relapsed, a second remission was obtained with combined therapy. In a review of 20 pregnancies with FVIII inhibitor, over a 15 year period, bleeding was controlled in all cases with no fatalities. Correct evaluation of coagulation screening tests, in particular, activated partial thromboplastin time, is essential.