The basics about hemophilia and other rare blood disorders.

Learn how these disorders are inherited or spontaneously developed, their symptoms, their treatment strategies, and tips for staying healthy.

Answering All of Your Questions

Comprehensive information for patients and caregivers about rare bleeding disorders is often hard to locate. You may find yourself looking through many resources to get what you need, or finding that most information is on hemophilia and von Willebrand’s disease and you don’t know whether it is relevant to you or your family member. 

This website aims to provide help in your search for information about hemophilia and other rare bleeding disorders all in one place. You will learn about why these disorders occur, whether they are inherited or occur spontaneously, the typical symptoms and bleeding tendencies, treatment strategies, complications, and tips for staying healthy. You will also learn about available resources and support that can help you start a plan of care.

Just because a disorder is rare does not mean it cannot be managed, it is just uncommon. That’s why this website also offers ways to connect you with people and resources that can help you manage a bleeding disorder. After all, just because you are unique doesn’t mean you are alone.

The Hemophilia and Rare Bleeding Disorders Medical Affairs Team at Novo Nordisk Inc. is happy to provide this information to you. Many dedicated healthcare professionals from the hemophilia treatment center (HTC) community and patients/caregivers like you have provided advice and editorial assistance to make sure this material is as relevant as possible. With their help, we plan to update this content as new information becomes available.

Our goal is to help provide education around these disorders, not to provide individual medical guidance. If you have one of the conditions in this website, talk with your healthcare professional or comprehensive treatment team. They can tell you more about your or your child’s specific disease and the treatment options that are appropriate and available based on the severity and symptoms.

How does my body normally stop bleeding?

Your body takes a series of complex steps to stop bleeding. It begins with small blood vessels called capillaries. When you are injured, such as from a cut or bruise, these capillaries break and you begin to bleed. The injured blood vessel then narrows (constricts) to slow down the flow of blood. 

Soon after that, small cells called platelets that are floating in your blood stick to the walls of the injured blood vessel. They also stick to each other and form an initial plug in the broken vessel wall.

That triggers a process called clotting, in which, initially, specific proteins like tissue factor, collagen and many others work together to create a firm blood clot like seen in the image below (primary hemostasis). This series of steps result in a protein called fibrin. Fibrin forms strands that link together, much like a net weaving in and around the clot. This net makes the blood clot stable and stops the bleeding until the vessel wall can heal.

Primary Hemostasis

The Clotting Process

Exposure of subendothelium at the site of vessel injury results in platelets sticking (adhesion), becoming active (activation) and forming a clump (aggregation). This results in the platelet plug that initially stops bleeding.

Take a look at the picture of the clotting process below (secondary hemostasis). The clotting factors are named using Roman numerals: factor I (1), factor II (2), factor III (3), factor IV (4), factor V (5), factor VI (6), factor VII (7), factor VIII (8), factor IX (9), factor X (10), factor XI (11), factor XII (12), and factor XIII (13). You can also see that the reactions in the process are linked. For example, early reactions must happen before the later ones can occur. This is sometimes called the “clotting cascade” because each step comes in a very specific order.

Secondary Hemostasis


What are rare bleeding disorders?

Rare bleeding disorders discussed in this website include those caused by either clotting factor deficiencies or those that are related to platelets. 

You may have a clotting factor deficiency or disorder if:

  • Your body is missing clotting factor
  • Your body does not make enough factor
  • The factor doesn’t work as it should

A list of the clotting factors and the associated disorders is shown below.

Factor Factor Name Deficiency/Bleeding Disorder
I Fibrinogen Afibrinogenemia; Dysfibrinogenemia
II Prothrombin Hypoprothrombinemia; Prothrombin Deficiency; Thrombophilia 

Thromboplastin; Tissue Factor

Congenital Antithrombin III Deficiency
IV Calcium None
V Proaccelerin; Labile Factor Parahemophilia; Owren’s Disease; Activated Protein C Resistance
VI Actually Activated Factor V None
VII Stable Factor Proconvetin Alexander’s Disease; Congenital proconvertin/Factor VII Deficiency
VIII Antihemophilic Factor A Hemophilia A; Classic Hemophilia
IX Antihemophilic Factor B; Christmas Factor Hemophilia B; Christmas Disease
X Stuart-Prower Factor Stuart-Prower Deficiency
XI Plasma Thromboplastin; Antecendent Hemophilia C
XII Hageman Factor Not typically associated with bleeding
XIII Fibrin Stabilizing Factor

Congenital Factor XIIIa/b Deficiency; Inherited Factor XIII Deficiency; Fibrin Stabilizing Factor Deficiency

von Willebrand Factor None von Willebrand Disease

For example, congenital hemophilia causes easy bleeding from too little factor VIII or factor IX activity. With other disorders, you may have a normal amount of clotting factor, but there are not enough platelets or they do not work properly.

  • Too few platelets or a platelet deficiency is known as thrombocytopenia (thrombocytes are another name for platelets)
  • A platelet function disorder is when there are enough platelets but the platelets don’t work

The disorders described in this website do not happen often. Many affect both males and females of all ages. Most of the time, these disorders are hereditary. This means the disorder was genetically passed from one or both parents to their child. But genes can also spontaneously change resulting in the disorder for some of these as well.

What happens if I have a rare bleeding disorder?

If you have a rare bleeding disorder, it does not mean you have to worry about every little cut or bruise. However, it does mean your body may have problems forming or maintaining a stable blood clot. The severity and location of the bleeding depends on which factor activity or platelet function is affected and for some more than others of the rare bleeding disorders, it more closely depends on how much of it you are missing. There may also be other things about your body that impact how much and where you bleed, including age, gender (males can bleed with circumcision, women can bleed excessively during menstrual periods and around pregnancy/delivery), having extremely flexible joints, and specific or repetitive activities. If you have a rare bleeding disorder, you do not bleed faster than someone without the disorder; it means you may bleed longer or be at risk for re-bleeding after the bleeding initially stops.

How do I stop bleeding if I have one of these disorders?

Treatment depends on the type and severity of your disorder and the type of bleed or procedure (dental, major or minor surgical, etc.). This can vary widely. It can be as simple as applying pressure to the site of bleeding. Or, you may need to replace the missing or deficient factor or platelets to stop bleeding. Depending on the details of your particular condition, your doctor can help you develop a treatment that’s right for you.

How do I find a specialist?

The most important thing you can do is to get educated about your bleeding disorder and learn what to look for when you try to find a treatment specialist or comprehensive Hemophilia Treatment Center (HTC) that is right for you.

Hematologists are physicians trained to treat disorders of the blood (“heme”). Pediatric hematologists typically complete a combined residency in children’s hematology and oncology, and then may choose to subspecialize in bleeding and clotting disorders. Adult hematologists are typically subspecialists of internal medicine. Within hematology some specialize in “benign” hematology (bleeding and clotting) and others specialize in “malignant” hematology (blood related cancers).

Hemophilia Treatment Centers (HTCs) are a specific comprehensive care approach featuring a multi-disciplinary team of experts lead by a hematologist that can explain your condition and provide the special care you may need. Having HTC specialists like physical therapists may be more important for some disorders that affect joints, such as hemophilia or congenital FVII deficiency. Nurses and social workers might be able to help with insurance, governmental supportive services, and issues with school or work.

An HTC or your hematologist may treat only children or adults, or both. If you need an invasive procedure such as surgery or dental work, your healthcare professional or HTC can help find specialists familiar with treating patients with bleeding disorders.

Because many of these disorders are inherited, you may want to ask your hematologist or HTC about genetic counseling. This is especially important for newborns and women/couples who are pregnant or who are planning to become pregnant. For some disorders, women are carriers, and for others, men and women can be carriers.

Some other things you can do:

  • Talk to your HTC or hematologist about getting a medical ID bracelet or tag that is appropriate for your condition and age.
  • Fill out an emergency information card and give it to the people who need to know, such as teachers and in some cases, employers. Like a medical ID bracelet, it provides valuable information in case of an emergency. An emergency information card should also be carried in your wallet.
  • If possible, avoid activities with a high risk of injury, such as contact sports. National Hemophilia Foundation (NHF) publishes a guide to “Pay it Safe” (see Document Downloads). Your doctor can help you choose activities that are right for you based on your age, fitness level and bleeding disorder.
  • Ask your doctor about any medicines (such as aspirin) and herbal supplements you take because some can affect blood clotting. Many over-the-counter medicines also contain blood thinning ingredients, so it’s important that you consult your healthcare professional or treatment center first.
  • Work with your healthcare professional or HTC team to develop a plan of exercise that can help strengthen your joints, and if necessary, help you lose weight. Added weight can cause problems with joints too depending upon your disorder. There are often changes in recommended treatment options approaches to engagement in leisure activities and sports, and new knowledge about how the bleeding tendency may change at different times in your life. So, stay educated about your or your child’s disorder.