Understanding Bleeding Disorders

Bleeding disorders are when the blood does not clot properly due to a deficiency or malfunction of clotting factor proteins or platelets. Bleeding disorders causes the body to bleed longer and more frequently than someone without a bleeding disorder. If left untreated, bleeding disorders can lead to chronic pain, arthritis, deformity, and disability.


Hemophilia is an inherited blood clotting disorder, occurring primarily in males, in which one or more of the 15 vital clotting proteins, called clotting factors, are either deficient or inactive.

If you will, imagine a set of dominos lined up on end, in a row, placed a little less than one domino length apart. Normally, if you pushed the first domino, you would have a cascade effect. However, if a domino is missing the sequence will be interrupted and some of the dominos will be left standing. The same is true of the clotting process. If one of the elements in the clotting process is missing or inactive, the next clotting factor in the sequence will not be triggered and the clotting process will stop.

Many believe that an individual with hemophilia will bleed harder or faster than normal, or that they can bleed to death from a small cut. THIS IS NOT TRUE! However, individuals with hemophilia, because of their inability to form a blood clot, will bleed longer. Small surface cuts and bruises are usually not a problem and normally clot on their own. Internal bleeding into a muscle, joint, organ, or head is more serious and typically requires treatment. Head injuries resulting in brain hemorrhage can also be life threatening.

Types of Hemophilia

Hemophilia A, also known as Classical Hemophilia or Factor VIII Deficiency, is the most common form of Hemophilia, comprising of about 80% of all individuals with Hemophilia. Hemophilia A is caused by a deficiency of a clotting protein called factor VIII.

Hemophilia B, also known as Christmas Disease or Factor IX Deficiency, is the second most common form of Hemophilia affecting the majority of the remaining 20% individuals with Hemophilia. Hemophilia B is caused by a deficiency of a clotting protein called factor IX.

Hemophilia C is a deficiency in clotting factor XI. Hemophilia C occurs predominantly in Jewish people of Ashkenazi decent.

Other Types of Hemophilia or even multiple clotting factor deficiencies do exist and are rare.

There are also other bleeding disorders that may produce symptoms similar to Hemophilia. Probably the most common inherited bleeding disorder, estimated to affect up to three percent of the population, is von Willebrand Disease, which is caused by a deficiency of a blood protein by the same name.

Von Willebrand Disease

Von Willebrand Disease is a hereditary deficiency or abnormality of the von Willebrand factor in the blood, a protein that affects platelet function. It’s the most common hereditary disorder of platelet function, affecting both women and men. The disease is estimated to occur in 1% to 2% of the population.

The disease was first described by Erik von Willebrand, a Finnish physician, who reported a new type of bleeding disorder among island people in Sweden and Finland.

In VWD, blood platelets don’t stick to holes in blood vessel walls. Platelets are tiny particles in the blood that clump together at the site of an injury to prepare for the formation of a blood clot. Von Willebrand factor causes them to bind to areas of a blood vessel that are damaged. If there is too little von Willebrand factor, or the factor is defective, platelets do not gather properly when a blood vessel is injured. Von Willebrand factor is found in plasma, platelets, and blood vessel walls. When the factor is missing or defective, the first step in plugging a blood vessel injury (platelets adhere to the vessel wall at the site of the injury) doesn’t take place. As a result, bleeding doesn’t stop as quickly as it should, although it usually stops eventually.

There are no racial or ethnic associations with the disorder. A family history of a bleeding disorder is the primary risk factor.

Women with Bleeding Disorders

Women of all ages who have von Willebrand disease, Hemophilia, or other bleeding disorders, have special issues with bleeding because of obstetric and gynecological issues. Prolonged menstrual bleeding and prolonged bleeding after childbirth or miscarriage can be a problem. Long, heavy menstrual flows often lead to low iron levels. Therefore, women with bleeding disorders should routinely be tested for anemia. During pregnancy, levels of factors VIII and IX and von Willebrand factor usually increase in women with bleeding disorders.

A woman with a bleeding disorder who becomes pregnant should see an obstetrician as soon as possible. This will ensure that the doctor can work with The Hemophilia & Thrombosis Center at OHSU to provide prenatal and postnatal care for the woman and her unborn baby. Miscarriages and abortions, even early in the course of a pregnancy, can result in prolonged bleeding for women with bleeding disorders. Women with bleeding disorders who know or think they are miscarrying, or who are choosing to end a pregnancy, should promptly seek medical care as soon as possible.