Review: Factor XI deficiency: review and management in pregnant women.

Factor XI deficiency is a rare disease found predominantly in Ashkenazi Jews. There is a poor correlation between factor XI level and bleeding in patients with factor XI deficiency. Individuals with severe factor XI deficiency are usually at risk of excessive bleeding after surgery and injury, particularly when trauma involves tissues rich in fibrinolytic activity. Women with partial or severe deficiency are at risk of excessive uterine bleeding during labor. The unpredictable nature of factor XI deficiency complicates management during pregnancy and delivery. This review gives an overview of the management of pregnant women with factor XI deficiency.