How many woman have hemophilia in the US?

Answer 1

The actual number of women diagnosed with hemophilia is very hard to pin down. Doctors do not even agree on what designates a female as having hemophilia. Some believe that both X chromosomes would need to have the mutation, while others diagnose using the clotting factor levels. Due to the occurrence of what some doctors call incomplete dominance by the non-affected X chromosome the mutation can lower a "carrier's" clotting factor below what would qualify any male as having hemophilia.