Do hemophilia carriers bleed?
Louis M. Aledort MOUNT SINAI SCHOOL OF MEDICINE Historically, hemophilia carriers have not been considered to be at risk for bleeding. This paper challenges the convention that these patients will be hemostatically normal if their factor levels exceed 40%. In this issue of Blood, Plug and colleagues report the largest survey of hemophilia carriers, either obligate or de novo; compare their factor levels to noncarriers; and demonstrate that, even at levels of coagulation factors considered hemostatic, these patients bleed substantially more than expected. Historically, hemophilia carriers were identified as either obligate, daughters of hemophiliacs, or de novo mutations, which are now more easily identified by genetic testing. Extrapolating from our knowledge of hemophilia, levels of factor greater than 25% to 30% have given clinicians confidence that hemostasis is essentially normal. Using questionnaires, 274 carriers and 245 noncarriers were analyzed. Information on bleeding patterns
MOUNT SINAI SCHOOL OF MEDICINE Historically, hemophilia carriers have not been considered to be at risk for bleeding. This paper challenges the convention that these patients will be hemostatically normal if their factor levels exceed 40%. In this issue of Blood, Plug and colleagues report the largest survey of hemophilia carriers, either obligate or de novo; compare their factor levels to noncarriers; and demonstrate that, even at levels of coagulation factors considered hemostatic, these patients bleed substantially more than expected. Historically, hemophilia carriers were identified as either obligate, daughters of hemophiliacs, or de novo mutations, which are now more easily identified by genetic testing. Extrapolating from our knowledge of hemophilia, levels of factor greater than 25% to 30% have given clinicians confidence that hemostasis is essentially normal. Using questionnaires, 274 carriers and 245 noncarriers were analyzed. Information on bleeding patterns, use of oral con
