What is hemophilia?

Hemophilia is a bleeding disorder. Children with hemophilia may bruise or bleed easily because they do not have enough of certain proteins that help blood clot.

The disease can be mild or severe, depending on your child’s level of clotting proteins. People with a mild case may not even know they have hemophilia until a major injury or a surgery causes severe bleeding.

Bleeding that starts inside the body, from injury or disease, may be a danger if:

  • Blood collects inside the body and causes swelling, pain and damage to nearby tissue
  • Bleeding affects the joints, causing pain or changing the joint’s shape or function
  • Bleeding inside the skull puts pressure on the brain
  • Bleeding causes swelling that blocks the airway
  • Types of hemophilia
    • Type A hemophilia: There is not enough of the protein called factor VIII (factor 8). This type is also called factor 8 deficiency.
    • Type B hemophilia: There is not enough of the protein called factor IX (factor 9). This type is also called factor 9 deficiency.
  • What causes hemophilia?

    Almost always, the disease is passed down from parents to children.

    Hemophilia happens because the gene that carries instructions for making clotting factor 8 or 9 does not work right. The gene is located on the X chromosome.

    Chromosomes come in pairs. Females have 2 X chromosomes. Males have 1 X chromosome and 1 Y chromosome. Only the X chromosomes carry the genes for these clotting factors.

    The disease is much more common in males. Males have hemophilia if they inherit an X chromosome carrying the abnormal gene from their mother.

    Females hardly ever have hemophilia. But females may have bleeding problems if they inherit an abnormal gene from both parents or if they carry 1 copy of the gene and have very low levels of clotting factors. Females who carry 1 copy of the abnormal gene can pass it on to their children, even if they are healthy.

Hemophilia at Seattle Children's

Seattle Children's is a hemophilia treatment center (HTC). This means we bring together a team of doctors, nurses and other healthcare experts who are experienced in treating children and teens with hemophilia. Our goal is to help your child lead an active, normal life.

The U.S. Centers for Disease Control and Prevention supports and funds a national networks of HTCs. Seattle Children’s has the only HTC for children and teens in Western Washington. We also serve Alaska, with a full range of services to diagnose and treat this disease.  

Our hemophilia team is part of our Cancer and Blood Disorders Center (CBDC). If you would like an appointment, ask your primary care provider to refer you. If you have a referral or would like a second opinion, contact the center at 206-987-2106.

Providers, see how to refer a patient.

  • The experts you need for complete care

    Our doctors are nationally known for treating children who have blood disorders. The doctors who will guide your child’s care are board certified in pediatric hematology. This means they are approved to give the special care your child needs and they constantly expand their knowledge about blood disorders.

    We offer a full range of services for children with hemophilia, such as clotting factors, physical therapy and medicine, including new nonfactor drugs. We also help your child prevent bleeding.

    We work with your family, your child and your child's primary doctor to get the right care and services for your child. We can also counsel parents who have hemophilia (or carry the gene) and want to know more about their risk of passing it to any future children.

    We care for your whole child. Your family has a full team behind you, including doctors, nurses, genetic counselors, social workers and specialists in physical therapy, nutrition and pain management. Read more about the supportive care we offer.

  • We treat your whole child

    Our specialty is treating children’s conditions while helping them grow up to be healthy and productive. 

    Our physician-scientists help set national standards for care of young people with blood disorders. We provide the most advanced treatments in our region.

    Children don’t react to illness, injury, pain and medicine in the same way as adults. They need – and deserve – care designed just for them. Our experience helps us recommend the right treatment at the right time to have the best results for your child and your family. We plan your child’s treatment based on years of experience and the newest research on what works best – and most safely – for children.

  • Research to advance care

    Our physician-scientists are working hard to improve treatments and outcomes for children with hemophilia and other blood disorders. We offer our patients the very latest treatments being explored in research studies called clinical trials. In the lab, researchers are making advances that could lead to new ways of treating this illness.

    Scientists at Seattle Children’s Research Institute have genetically reprogrammed immune system cells (human plasma B cells) to release the factor 9 clotting protein that is lacking in patients with hemophilia B. Because they have long life span, these B cells could be the ideal cell type to treat diseases where patients cannot make a needed protein, like clotting factor.

    Dr. Carol Miao’s lab is working on new approaches that include:

  • Support for your whole family

    Having a child with hemophilia affects the whole family. We help by offering same-day appointments for children with urgent needs. If needs are not urgent, most new patients are seen within 1 or 2 weeks.

    During visits, we take time to explain your child’s condition. We help you fully understand your treatment options and make the choices that are right for your family.

    Together with the Washington Center for Bleeding Disorders at Bloodworks Northwest, we provide 24-hour telephone support by hemophilia nurse specialists.

    Our child life specialists and social workers help your child and your family through the challenges of this condition. We connect you to community resources and support groups. Each summer doctors from our team provide medical coverage for the week-long hemophilia family camp called Camp I-Vy.

    At Seattle Children's, we work with many children and families from around the Northwest and beyond. Whether you live nearby or far away, we can help with financial counseling, schooling, housing, transportation, interpreter services and spiritual care. Read about our services for patients and families.

Symptoms of Hemophilia

The main symptom of hemophilia is that once bleeding starts, a child bleeds longer than normal.

People with mild hemophilia may not even know they have the disease until a major injury or surgery causes bleeding problems.

But someone with severe hemophilia may often bleed without any known reason or injury. This is called "spontaneous" bleeding. Sometimes this type of bleeding happens in a joint, like the knee or elbow, and can be quite painful.

Symptoms of hemophilia may include:

  • Nosebleeds
  • Bruising, especially a large, lumpy bruise
  • Bleeding for no known reason
  • Blood in the pee or poop
  • Bleeding that does not stop after getting a cut, having a tooth pulled or having surgery
  • Bleeding that does not stop after circumcision
  • Bleeding into a joint, which can cause tightness, swelling and pain

Diagnosing Hemophilia

If your child seems to have a bleeding problem, the doctor will:

  • Ask about your child's bleeding.
  • Ask about your family history of unusual bleeding or bruising.
  • Check your child for signs of health problems.
  • Test your child’s blood to see how well it can clot. This includes checking levels of factor 8 and factor 9.

Even if there are enough clotting factors to be considered "mild" hemophilia, a child may have severe symptoms. Your child's doctor can explain what the diagnosis means for your child.

  • Genetic counseling

    We also advise parents who have hemophilia (or carry the gene) and want to know more about their risk of passing it to their children. This is called genetic counseling.

    Our genetic counselors can talk with you about the pros and cons of genetic testing. They explain test results and your chance of having a child with hemophilia in a future pregnancy.

    Our genetic counselors also will give you information about your child’s condition. Counseling can help you make informed decisions about family planning and your child’s treatment.

Treating Hemophilia

Your child’s care plan depends on their illness. We watch your child closely and recommend the right treatments at the right time. Our treatment goals are to:

  • Control your child’s hemophilia
  • Manage any other health problems it causes

At Seattle Children’s we offer these treatment options:

  • Clotting factor

    To treat hemophilia, doctors give your child the clotting factor they need: factor 8 or factor 9.

    The factor is mixed with fluid and given through a tube into your child’s vein. This is called an infusion or intravenous (IV) treatment.

    How often your child needs treatment depends on their disease. In mild cases, they may need clotting factors only when they have a bleeding problem.

    In severe cases, a child will get regular infusions, as often as 3 or 4 times a week. Some children may be able to use clotting factor mixtures that can be taken less often.

    Your child can get infusions without having to spend a night in the hospital.

    • Our outpatient infusion unit is staffed by expert nurses and is open on weekends.
    • We teach patients and families to mix and give infusions at home. This may be done with a butterfly needle or an intravenous (IV) line that we place before a child goes home.

    Our goal is that all children with hemophilia learn to self-infuse before adulthood so they have the skills to treat themselves at home.

  • Nonfactor therapies

    A new drug (emicizumab) that boosts blood clotting may be an option for some children with hemophilia A. It is longer lasting than factor 8, so children need fewer infusions. Another benefit is that nonfactor treatments do not prompt the immune system to reject them, as sometimes happens when people are given factor 8. The U.S. Food and Drug Administration (FDA) has approved emicizumab to treat children, teens and adults.

    Other nonfactor treatments (fitusiran and concizumab) reduce anticlotting activity in the body. They are under study in clinical trials. Research studies of gene therapy may be an option for patients 18 years and older within 2 years.

    We offer clinical trials:

    • Of new options developed here at Seattle Children’s
    • In collaboration with other investigators around the country
    • Of new treatments developed by pharmaceutical companies

    Your child’s doctor will talk with you about any new treatment options that might help your child. Then you can decide whether you want to take part.

  • Physical therapy

    Keeping muscles, bones and joints strong is important for young people with hemophilia. Our physical therapist sees your child every year to:

    • Check their growth and strength
    • Find any areas that need strengthening
    • See if they need therapy to keep their joints healthy and working well

    If your child has had bleeding in a joint or muscle, they are at risk of losing muscle strength, flexibility and mobility. Your child will work with a physical therapist to help fully recover and reduce the chance of it happening again.

  • Medicine to reduce bleeding

    Medicines that help keep blood clots from breaking down are called antifibrinolytic (AN-te-fi-BRIN-o-LIT-ik). They are used mainly to reduce bleeding after:

    • An injury
    • Having a tooth pulled
    • Surgery

    Children with some mild forms of hemophilia may take medicine to help increase clotting. It is called desmopressin (brand name Stimate). The doctor will try a test dose to see if it works well for your child. If it does, your child may take it before any planned surgery or dental work.

  • Preventing bleeding

    Children with hemophilia can lead active, normal lives. We help you and your child lower the risk of bleeding problems.

    Your child’s doctor will recommend that your child:

    • Avoid certain contact sports, such as tackle football, boxing and hockey.
    • Avoid medicines that increase bleeding, such as aspirin and ibuprofen (Advil). Your child's doctor can give you details about which medicines to avoid.
    • Take extra good care of their teeth to help avoid dental work that might cause bleeding. When a child does need dental work, we often work closely with Seattle Children's Dental Medicine to give factor treatment right before a visit to the dentist.
    • Consider wearing a medical identification bracelet (like MedicAlert) so healthcare providers are aware your child has bleeding problems.

Contact Us 

If you would like an appointment, ask your child’s primary care provider to refer you.

If you have a referral or would like a second opinion, contact the Cancer and Blood Disorders Center at 206-987-2106 or by email.

Providers, see how to refer a patient.

Related Links

Paying for Care

Learn about paying for care at Seattle Children’s, including insurance coverage, billing and financial assistance.

For Healthcare Professionals