with milder forms of vW are currently
The role and importance of clotting factors
undiagnosed.
Certain proteins found in the blood are
strong evidence that many women
needed to stop bleeding and are known as
What is von Willebrand factor, and how does it work in the body?
clotting factors. Clotting factors work
Basics of bleeding
should, is missing, or is present only at low
To understand bleeding disorders better, it is useful to know more about blood and how it functions in the body. Blood is a complex fluid which is carried in arteries, veins and capillaries. When one of these vessels is injured, a small hole forms, allowing blood to flow out. Three stages follow: ·
in stage 1, the injured blood vessel contracts to slow down the flow of blood
·
in stage 2, blood cells – known as platelets – form a plug to stop the blood flowing out of the hole
·
in stage 3, a blood clot – made of a jelly-like substance – acts like glue and completely covers the hole, preventing any more blood from spilling out.
together with other proteins and cells in the blood to help stop bleeding. When one of the clotting factors does not work as it levels, the blood does not clot the way it should. When this occurs, we say the individual has a ‘bleeding disorder’. Von Willebrand factor is a blood protein that acts like a ‘glue’ to make platelets stick to the areas of blood vessel that are damaged. If there is not enough von Willebrand factor in the blood, the platelets don’t ‘stick’ properly which means bleeding will continue for longer than it should. When someone with vW is injured and bleeds, the bleeding takes longer to stop because clots form more slowly. This is especially true in the delicate tissues that line the nose, mouth, reproductive organs and digestive tract. Von Willebrand factor also acts as a ‘carrier’ of clotting factor VIII. This means
Bleeding can happen anywhere in the body . Bleeding outside the body from a cut or graze is easy to see. It is also easy to see the result of bleeding just under the skin because a bruise forms. Sometimes a person can bleed from the
that some people with vW may also have a low amount of factor VIII. Factor VIII is another protein needed for blood clotting. This protein is the one commonly missing, or at low levels, in people with haemophilia.
nose or mouth. Bleeding can also occur inside the body where it cannot be seen, such as into joints or organs.
Types of von Willebrand’s vW is divided into ‘types’ according to whether someone has a low amount of von Willebrand factor or has a type of von Willebrand factor that does not work properly, or both. Knowing the type of
6 A guide for women living with von Willebrand’s