F8 and hemorrhagic disease: The proband’s mother and maternal grandmother was a heterozygous carrier, with normal thrombin time (TT) and FVIII activity at the edge of the Reference range, It has been reported that about 30% of F8 heterozygous women with factor VIII coagulation activity is less than 40% and have bleeding disorders (even if the affected family members are slightly involved) [15], carriers are more likely to bleed than unaffected women [5].