What is Hemophilia A?
Hemophilia A is an inherited disease characterized by spontaneous or prolonged hemorrhages due to factor VIII deficiency, an enzyme of the coagulation cascade. The age of onset is neonatal or infantile.
Hemophilia A follows an X-linked pattern of inheritance. Carrier females have a 1 in 2 chance of transmitting the pathogenic variant in each pregnancy: sons who inherit the pathogenic variant will be affected; daughters who inherit the pathogenic variant are carriers. Affected males transmit the pathogenic variant to all of their daughters and none of their sons.
What is the next step if I’m a carrier of Hemophilia A?
If you are found to be a carrier of Hemophilia A, it is important that your partner be tested for the same genetic disorder.
What if my partner is not a carrier?
If your partner’s test for Hemophilia A is negative, the chance to have an affected child is low. However there is currently no test able to detect all existing mutations, so there is always a residual risk that the person who has done the test is a carrier of other less frequent mutations.
What if both me and my partner are carriers of Hemophilia A?
When both parents are carriers of Hemophilia A, the probability of having a child with this disease is 25%.
We recommend that you discuss your results with your doctor or genetic counselor in order to know more about reproductive options.