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

Objective: To review the clinical problems related to the inhibitor of factor VIII (FVIII) in pregnancy.

Design: Retrospective analysis.

Setting: Haemophilia and haemotology centres.

Population: Patients registered and followed up at the centres.

Methods: Data were collected from the Italian Haemophilia Register of acquired FVIII inhibitor.

Results: 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.

Conclusions: 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.