Outcomes and management of pregnancy in women with bleeding disorder of unknown cause.

BACKGROUND: patients with a bleeding tendency with normal laboratory tests have been described as having an unclassified bleeding disorder or bleeding disorder of unknown cause (BDUC). There is very little data available on how to manage pregnancy. OBJECTIVES: a study of management and outcomes of these patients at 4 United Kingdom haemophilia comprehensive care centres. METHODS: retrospective case note review from 2010-2020. RESULTS: 60 deliveries in 36 patients were recorded. The median International Society on Thrombosis and Haemostasis bleeding assessment tool score was 9. In 54 cases where data was available, the odds ratio for post-partum haemorrhage (PPH) was 6.3 for no primary haemostatic prophylaxis versus prophylaxis (95% confidence interval 1.2 - 34.2, p<0.05); 16/45 (36%) versus 7/9 (78%) PPH incidence for the groups respectively. Haemostatic prophylaxis was with tranexamic acid but some patients received desmopressin or platelet infusions. Secondary PPH was seen in 5/60 (8%) of cases. No neonatal bleeding complications or maternal thromboembolic complications were noted. Avoidance of regional anaesthesia and fetal delivery precautions were commonly advised, but in the small number of cases where they occurred no complications were noted. CONCLUSIONS: Despite haemostatic prophylaxis PPH was commonly seen. Further prospective studies of BDUC patients are required to determine optimal management in pregnancy as well as determine the pathophysiological basis of bleeding.