Your genes, or other causes such as medical conditions or medicines, can cause bleeding disorders. Sometimes a cause may not be known. Any problem that affects the function or number of clotting factors or platelets can lead to a bleeding disorder.
Bleeding disorders can be caused by genes that are passed down from your parents. Your genes provide instructions for how each clotting factor is made. If there is a mutation in the gene, then the clotting factor may be made incorrectly or not at all.
How is hemophilia inherited?
Inherited hemophilia is caused by a defect in one of the genes for clotting factor VIII or IX. These genes are located on the X chromosomes. A male who has a hemophilia gene on his X chromosome will have hemophilia. When a female has a hemophilia gene on only one of her X chromosomes, she is a hemophilia carrier. If a female inherits a hemophilia gene from both parents, she can get hemophilia, but this happens rarely. Anyone with a hemophilia gene can pass the gene to their children.
Medical conditions, procedures, or medicines can cause bleeding disorders. Some medical conditions and medicines that lead to bleeding disorders cause your body to produce proteins, called antibodies or inhibitors, that can attack clotting factors.
Other medical conditions may cause your body to stop making clotting factors or to make too little of them. Certain medical devices or procedures can also affect clotting factors, as the pumping of blood through the area can affect the amounts of clotting factors.
Learn more in Risk Factors.