The spectrum of bleeding in women and girls with haemophilia B.

Although hemophilia B affects 1 in 25,000 males there may be 3 female hemophilia B carriers per affected male. This clinical review highlights the unique challenges faced by hemophilia B carriers including the under-recognition of bleeding symptoms associated with and without FIX deficiency, discrepancies in correlation between genotype and bleeding phenotype and therapeutic considerations utilizing clinical vignettes of common scenarios.