Bleeding Disorders

Also known as Hemophilia, von Willebrand Disease, Coagulation Disorders, Blood Clotting Disorders, Clotting Factor Deficiencies
Bleeding disorders are rare disorders affecting the way the body controls blood clotting. If your blood does not clot normally, you may experience problems with bleeding too much after an injury or surgery. This health topic will focus on bleeding disorders that are caused by problems with clotting factors, including hemophilia and von Willebrand disease.

Clotting factors, also called coagulation factors, are proteins in the blood that work with small cells, called platelets, to form blood clots. Any problem that affects the function or number of clotting factors or platelets can lead to a bleeding disorder.

A bleeding disorder can be inherited, meaning that you are born with the disorder, or it can be acquired, meaning it develops during your life. Signs and symptoms can include easy bruising, heavy menstrual periods, and nosebleeds that happen often. Your doctor will review your symptoms, risk factors, medical history, and blood test results to diagnose a bleeding disorder.

Your doctor may recommend medicines or clotting factor replacement therapy to treat the bleeding disorder. Some bleeding disorders are lifelong conditions, and some can lead to complications. Even if you do not need medicine to treat the bleeding disorder, your doctor may recommend taking precautions before a medical procedure or during a pregnancy to prevent bleeding problems in the future.

Explore this Health Topic to learn more about bleeding disorders, our role in research and clinical trials to improve health, and where to find more information.

Types - Bleeding Disorders

Bleeding disorders can be inherited, or they can be acquired, meaning you develop them during your lifetime. Acquired bleeding disorders are more common than inherited bleeding disorders.

Acquired bleeding disorders
- Bleeding Disorders

You may develop a bleeding disorder if something in your body, such as a disease or a medicine, causes your body to stop making blood clotting factors or causes the blood clotting factors to stop working correctly. In addition, problems with your blood vessels can lead to bleeding.

Acquired bleeding disorders include:

  • Disseminated intravascular coagulation (DIC)
  • Liver disease-associated bleeding
  • Vitamin K deficiency bleeding
  • Von Willebrand disease and hemophilia, two conditions that are most often inherited, may also develop as a result of a medical condition.
  • Other, rarer types of acquired bleeding disorders include deficiencies of certain factors, such as factor I, II, and V, that are named for the clotting factor causing the problem.
  • Rarely, tangles of blood vessels, called arteriovenous malformations, can form in the brain or elsewhere in the body and lead to bleeding. These tangles may form before birth or later in life.

Inherited bleeding disorders
- Bleeding Disorders

Inherited bleeding disorders include the following:

  • Combined deficiency of the vitamin K–dependent clotting factors (VKCFDs), caused by a problem with clotting factors II, VII, IX, and X.
  • Hemophilia A, a condition in which you are missing clotting factor VIII or have low levels of clotting factor VIII. Hemophilia A is the most common type of hemophilia.
  • Hemophilia B, a condition in which you are missing clotting factor IX or have low levels of clotting factor IX.
  • Hemophilia C, a rare condition also known as factor XI deficiency.
  • Von Willebrand disease (VWD), the most common inherited bleeding disorder. The different types of VWD are numbered based on how common the condition is and how severe the symptoms are. For example, VWD 1 is the most common, and symptoms are usually mild, and VWD 3 is uncommon with symptoms that are usually severe.
  • Other inherited bleeding disorders include other factor deficiencies, such as I, II, V, V + VIII, VII, X, XI, or XIII deficiencies. These rare bleeding disorders are named by the clotting factor causing the problem.
  • Hereditary hemorrhagic telangiectasia is a rare inherited condition in which your blood vessels get tangled in different parts of the body, which can lead to bleeding.

Causes - Bleeding Disorders

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.

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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 Mutations in the gene, then the clotting factor may be made incorrectly or not at all.

How is hemophilia inherited?

Other causes
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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.

Look for
- Bleeding Disorders

  • Treatment will discuss medicines and clotting factor replacement therapy that your doctors may recommend if you are diagnosed with a bleeding disorder.

Risk Factors - Bleeding Disorders

You may have an increased risk for bleeding disorders because of your age, family history and genetics, other medical conditions and medicines, and your sex.

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Bleeding disorders can happen at any age. However, newborns are more likely than adults to develop vitamin K deficiency bleeding. Acquired hemophilia A is more common among older people.

Family history and genetics
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Bleeding disorders may run in families. You are at an increased risk of having a bleeding disorder if one or both of your parents have the disease.

Other medical conditions
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Certain diseases or medical conditions can increase your risk for an acquired bleeding disorders, such as:

  • Blood transfusions
  • Bowel diseases or bowel surgery
  • cancer
  • congenital or acquired heart diseases
  • Hypothyroidism
  • Immune disorders, including Autoimmune diseases such as rheumatoid arthritis or lupus
  • Infections
  • Liver disease
  • Lymphoproliferative disorders, such as certain types of leukemia
  • Pregnancy
  • Postpartum bleeding, which can use up the body’s clotting factors too quickly
  • Skin conditions
  • Trauma, or severe injury, to the brain or body

Certain treatments for medical conditions can also increase risk, including:

  • Antibiotics
  • Blood thinner medicines, also called anticoagulants, that are used to help prevent Blood clots from forming inside the blood vessels
  • Devices that increase blood flow, such as ventricular assist devices
  • Interferon alpha, a medicine to treat certain types of cancer
  • Surgeries, such as heart surgeries that use a heart-lung bypass machine, that can lead to acquired von Willebrand disease

- Bleeding Disorders

Hemophilia is much more common in men than in women. However, women are at increased risk for bleeding disorders, such as acquired hemophilia, during and after pregnancy.

Screening and Prevention - Bleeding Disorders

It is not typical to screen for bleeding disorders, unless you are having certain types of major surgery or have known risk factors. Your doctor may do a blood test. If you are diagnosed with a bleeding disorder, your doctor may discuss your risk of passing your condition on to a future child.

Prenatal screening
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Depending on your risk factors, your doctor may recommend screening your baby during your pregnancy using chorionic villus sampling (CVS). During CVS, the doctor threads a thin tube through the vagina to the placenta, where a tissue sample is collected using gentle suction. This test may be offered at 9 to 11 weeks to look for the hemophilia gene among women who are known hemophilia carriers, such as with hemophilia A or B. At a later stage during pregnancy, or after the baby is born, your doctor can do a blood test from the umbilical cord.

See Diagnosis for more information about diagnostic tests.

Prevention strategies
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Inherited bleeding disorders, such as inherited or acquired hemophilia and von Willebrand disease, cannot be prevented. Couples who are planning to have children and know that they are at risk of having a child with a bleeding disorder may want to meet with a genetic counselor. A genetic counselor can answer questions about the risk.

Newborns are at an increased risk of vitamin K deficiency bleeding. To prevent a bleeding disorder caused by vitamin K deficiency, your baby will most likely get a vitamin K shot right after birth.

Look for
- Bleeding Disorders

  • Diagnosis will explain tests that your doctor may use to diagnose types of bleeding disorders.
  • Living With will discuss what your doctor may recommend to prevent your bleeding disorder from recurring, getting worse, or causing complications.
  • Research for Your Health will explain how we are using current research and advancing research to prevent bleeding disorders.
  • Participate in NHLBI Clinical Trials will discuss our open and enrolling clinical studies that are investigating prevention strategies for bleeding disorders.

Signs, Symptoms, and Complications - Bleeding Disorders

signs, symptoms, and complications may differ depending on the type of bleeding disorder, its cause, and whether the disorder is mild or more serious. Signs and symptoms may be obvious soon after a child is born or not until adulthood. People who have a mild bleeding disorder may not have any signs or symptoms until they are injured or have a medical procedure.

Signs and symptoms
- Bleeding Disorders

Signs and symptoms of bleeding disorders may include:

  • Blood in urine or stool
  • Excessive bleeding that does not stop with pressure and may start spontaneously, such as with nosebleeds, or bleeding after a cut, dental procedure, or surgery
  • Frequent, large bruises
  • Heavy bleeding after giving birth
  • Heavy menstrual bleeding, which includes menstrual bleeding that often lasts longer than seven days or requires changing sanitary pads or tampons more than every hour
  • Petechiae, or bleeding under the skin causing tiny purple, red, or brown spots
  • Redness, swelling, stiffness, or pain from bleeding into muscles or joints, which is particularly common with inherited hemophilia
  • Umbilical stump bleeding that lasts longer than what is typical for newborns—about one to two weeks after the umbilical cord is cut—or that does not stop

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Severe bleeding disorders can cause serious and life-threatening problems, including:

  • Bleeding in the brain or central nervous system, which can cause a hemorrhagic stroke
  • Bleeding in the throat that can cause swelling and block the windpipe
  • Bleeding into the abdomen, which can cause inflammation and damage to nerves
  • Damaged joints from bleeding into joints over time, especially for people who have inherited hemophilia. This can also cause Chronic pain.
  • Hard masses in the bones from pooled blood
  • Miscarriages

Look for
- Bleeding Disorders

  • Diagnosis will explain tests used to detect signs of bleeding disorders and help rule out other conditions.
  • Treatment will discuss treatment and related complications or side effects.
  • Living With will discuss how to reduce the chance of complications and how complications may be treated.

Diagnosis - Bleeding Disorders

It may be possible for your doctor to diagnose your bleeding disorder, its severity, and whether it is inherited or acquired based on your signs and symptoms, risk factors, medical and family history, a physical exam, and blood tests.

Medical history
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To help diagnose a bleeding disorder, your doctor may ask you questions such as these:

  • Do you have blood in your urine or stool?
  • Does your family have a history of bleeding disorders, bleeding events, or blood clots?
  • Do you have a history of miscarriage or postpartum bleeding?
  • Do you have symptoms of other medical conditions associated with bleeding disorders?
  • How long do your menstrual period lasts, and how many sanitary pads or tampons you use per day during your period?
  • How often do you bruise or bleed, and how long does the bleeding last?
  • What prescription or over-the-counter medicines, such as aspirin, do you take?
  • Do your gums often bleed, or do you bleed a lot following dental procedures?

Physical examination
- Bleeding Disorders

Your doctor will do a physical exam to look for signs of a bleeding disorder, such as bruising or petechiae. Your doctor may also look for signs of medical conditions that can cause bleeding disorders or signs of other medical conditions that can cause similar symptoms. Depending on the reason for your visit, the doctor may look for signs of bleeding-related complications, by looking for swelling and checking your blood pressure, heart rate, and breathing.

Diagnostic tests and procedures
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To diagnose a bleeding disorder and whether it may be inherited or acquired, your doctor may order one or more of the following tests.

  • A complete blood count (CBC) to measure many different parts of your blood, such as the number of blood cells and platelets. If the number of platelets is too low, you may have a platelet disorder instead of a clotting factor disorder.
  • A partial thromboplastin time (PTT) test, also called an activated PTT (aPTT), to measure how long it takes blood to clot. It can help determine whether certain clotting factors are involved.
  • A prothrombin time (PT) test is another test to measure how long it takes blood to clot. It measures clotting factors that the PTT test does not.
  • A mixing test to help determine whether the bleeding disorder is caused by antibodies blocking the function of clotting factors, such as with autoimmune disorders or acquired hemophilia.
  • Von Willebrand factor (vWF) tests to measure the amount of von Willebrand factor, whether the factors are working correctly, or which type of VWD you have.
  • Clotting factor tests, also called factor assays or a coagulation panel, to determine whether certain clotting factors are missing or show up at lower levels than normal, which can indicate the type and severity of the bleeding disorder. For example, if you have very low levels of clotting factor VIII, you may have hemophilia A.
  • A Bethesda test to look for antibodies to factor VIII or IX
  • Factor XIII antigen and activity assays to look for factor XIII deficiency
  • Genetic testing to determine if particular genes may be causing the bleeding disorder. Your doctor may refer you or your child to a specialist in genetic testing.

For some bleeding disorders, such as hemophilia, the clotting factor test can tell you how severe the disorder is. Below are possible results from testing for hemophilia A:

  • Severe hemophilia A: <1% of factor VIII detected
  • Moderate hemophilia A: 1% to 5% of normal factor VIII levels
  • Mild hemophilia A: 6% to 30% of normal factor VIII levels

For hemophilia A, the amount of factor VIII is measured and compared to normal amounts. If you have mild hemophilia, you would have 30% or less of the factor VIII levels that a person without a bleeding disorder would have. If you have moderate hemophilia, you would have less than 6% of normal factor VIII levels. If you have severe hemophilia, there would be no detectable levels of factor VIII.

Tests for other medical conditions
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Because bleeding can be caused by other medical conditions, your doctor may do tests or procedures to look for conditions that can cause acquired bleeding disorders, such as:

  • A blood test called a liver panel, to measure substances in the blood that depend on liver function
  • A lupus anticoagulant test, to look for signs of lupus
  • A pregnancy test
  • Procedures, such as a pelvic exam, Pap test, ultrasound, or biopsy of the lining of the uterus, to look for signs of disorders that can cause heavy menstrual bleeding

- Bleeding Disorders

Treatment - Bleeding Disorders

Treatment for bleeding disorders will vary depending on the disorder and may include medicines and factor replacement therapy. Your treatment may be every day to prevent bleeding episodes, or as needed when you plan for surgery or have an accident. You may not need treatment if your bleeding disorder is mild.

Your healthcare team
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Bleeding disorders affect many parts of the body, so you will need a team of different doctors for your care. This includes a hematologist, a doctor who specializes in blood disorders. It may also include a specialized nurse, physical therapist, and social worker. You and your healthcare team may develop a treatment plan that is best for you depending on the bleeding disorder.

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Medicines to treat bleeding disorders may include the following.

  • Antifibrinolytic agents, such as tranexamic acid, to treat bleeding after childbirth or during procedures such as those involving dental work
  • Birth control pills to treat heavy menstrual bleeding for women with von Willebrand disease
  • Desmopressin (DDAVP), a human-made hormone, to treat minor bleeding in hemophilia or VWD.
  • immunosuppressive medicines, such as prednisone, to block production of antibodies in acquired bleeding disorders. Side effects can include infections and diabetes.
  • Vitamin K supplement, to treat vitamin K deficiency bleeding

Factor replacement therapy
- Bleeding Disorders

Factor replacement therapy is a type of treatment where clotting factors that are from blood donations or made in a lab are given to replace the missing clotting factor. Your doctor may recommend factor replacement therapy when you experience bleeding or to prevent bleeding from occurring. Treatment with replacement therapy on a regular basis to prevent bleeding is called prophylactic treatment. Prophylactic treatment is most often used for severe bleeding disorders.

Factor replacement therapy may include:

  • Bypassing medicines to treat antibodies. These medicines add other types of clotting factors to help your blood clot. This treatment can raise the risk of blood clots forming in the blood vessels.
  • Clotting factor concentrates to replace the missing clotting factor in inherited bleeding disorders. This treatment can raise the risk of antibodies forming in the blood. Sometimes factor concentrates are used in higher doses to treat bleeding disorders related to antibodies.
  • Fresh frozen plasma, from human blood, to provide clotting factors. It is used for bleeding disorders caused when multiple clotting factors are missing, such as liver disease-associated bleeding.

Learn more about how complications are managed in the Living With section.

Look for
- Bleeding Disorders

  • Research for Your Health will explain how we are using current research and advancing research to treat people who have bleeding disorders.
  • Participate in NHLBI Clinical Trials will discuss our open and enrolling clinical studies that are investigating treatments for bleeding disorders.
  • Living With will explain what your doctor may recommend including lifestyle changes and ongoing care to improve your quality of life and prevent complications.

Living With - Bleeding Disorders

If you are diagnosed with a bleeding disorder, it is important that you follow your treatment plan, receive routine care, maintain a healthy lifestyle, and learn how to lower your risk of complications. Know what steps you need to take if you have a child with a bleeding disorder. Women with bleeding disorders have unique needs, especially during pregnancy.

Receive routine follow-up care
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How often you see your doctor will depend on the severity of your bleeding disorder, your symptoms, and which treatments you are using. Even if you do not have symptoms and are not undergoing a treatment, you should see your doctor for ongoing care.

  • Follow your treatment plan as directed by your doctor to prevent complications. Your treatment plan may change over your lifetime.
  • Keep all your medical appointments.
  • Talk to your doctor about hemophilia treatment centers, which provide care for people who have bleeding disorders.
  • Tell your doctor about any changes in your symptoms. Your doctor may do tests to determine whether your treatment plan needs to be adjusted.

Return to Treatment to review treatment options.

Monitor your condition
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After starting treatment, your doctor will check to make sure it is working. This may include blood tests right after treatment, and then regularly to see whether there is a change in the levels of clotting factors or antibodies within your blood.

Replacement therapy can cause major complications, which can include:

  • Viral infections, such as hepatitis C, if the clotting factors come from human blood products. This risk is now very low in fresh frozen plasma and platelet concentrates, because all donors are screened for hepatitis C. The risk is nearly zero for clotting factor concentrates, which are treated to kill viruses or are made in the laboratory instead of from human blood.
  • Antibodies, which can form because of treatment with clotting factor concentrates. The formation of antibodies is a complication that occurs more often in people who have severe bleeding disorders and those who have had high doses of replacement therapy. Your doctor may test you for antibodies regularly or if your treatment does not seem to be working as well. If you have antibodies, your treatment might change to include higher doses of replacement therapy or a different type of replacement therapy called bypassing agents.

Return to Diagnosis to review the types of blood tests used for bleeding disorders.

Adopt healthy lifestyle changes
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Your doctor may recommend that you adopt lifelong heart-healthy lifestyle changes to improve your health and help reduce your risk of ischemic heart disease, which is very difficult to manage in people who have a bleeding disorder.

A healthy lifestyle includes:

Prevent complications over your lifetime
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To prevent or treat complications, your doctor may recommend the following.

  • Follow directions for treatment. Prophylactic treatment with replacement therapy is meant to lower the chance of bleeding and bleeding-related complications, such as joint damage. Even if you have joint damage, prophylactic treatment may help reduce pain.
  • Take pain medicine and do physical therapy for pain and swollen joints. Your doctor may also recommend anti-inflammatory medicine or surgery for damaged joints.

Learn the warning signs of serious complications and have a plan
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Bleeding in the throat, abdomen, or brain can be a life-threatening complication of hemophilia. Call 9-1-1 if you or someone else has recently had an injury to the head, throat, or abdomen, or has the following.

Signs and symptoms of bleeding in the brain, which include:

  • Convulsions or seizures
  • Headache or neck pain and stiffness
  • Memory loss or confusion
  • Repeated vomiting
  • Severe pain in your head
  • Sudden changes in your vision
  • Sudden inability to move your legs or arms

Signs and symptoms of bleeding in the throat or digestive system, which include:

  • Bright red blood in your stool or black, tarry stools
  • Bright red vomit or vomit that looks like coffee grounds
  • Difficulty breathing
  • Pain in your abdomen
  • Sore throat or difficulty swallowing

Children and bleeding disorders
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If you have a child with a bleeding disorder, talk with your child’s healthcare team. Get education and support from a hemophilia treatment center, support groups, and camps.

For children with moderate to severe hemophilia, your doctor may recommend replacement factor therapy on a regular schedule to help prevent spontaneous bleeding and to reduce bleeding from trauma. To help your child stay safe, your doctor may tell you to:

  • Consider a medical ID bracelet or necklace for your child to wear.
  • Learn how to examine your child for and recognize signs of bleeding.
  • Provide children with extra protection in the home and elsewhere with kneepads, elbow pads, protective helmets, safety belts, and straps.

Talk with your child’s teachers and coaches about when to contact you and when to call 9-1-1.

Women and bleeding disorders
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Women who have a bleeding disorder have unique risks, such as heavy menstrual bleeding and pregnancy complications. Genetic carriers for hemophilia can also have bleeding complications, such as after childbirth, even though they may not have other symptoms. During pregnancy and childbirth and after childbirth, your doctor may suggest changes in your treatment plan and coordinating care with your hemophilia treatment center.

Learn about other precautions to help you stay safe
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To stay safe living with a bleeding disorder:

  • Talk to doctors, dentists, employers, loved ones, and others about your bleeding disorder and what to do in case emergency action should be taken.
  • Talk to your doctor about preparing for surgery, as well as the potential risks and complications. You may need to take medicine or have replacement therapy.
  • Talk to your doctor or pharmacist about which medicines are safe for you to take. Some medicines, such as aspirin or other pain relievers, increase the risk of bleeding.

Research for Your Health

The NHLBI is part of the U.S. Department of Health and Human Services’ National Institutes of Health (NIH)—the Nation’s biomedical research agency that makes important scientific discovery to improve health and save lives. We are committed to advancing science and translating discoveries into clinical practice to promote the prevention and treatment of heart, lung, blood, and sleep disorders including bleeding disorders. Learn about current and future NHLBI efforts to improve health through research and scientific discovery.

Improving health with current research
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Learn about the following ways the NHLBI continues to translate current research into improved health for people with bleeding disorders. Research on this topic is part of the NHLBI’s broader commitment to advancing blood disorders and blood safety scientific discovery.

  • NHLBI State of the Science Workshop on Factor VIII antibodies. We held a workshop in May 2018 to convene hemophilia experts and discuss future directions for research. Discussions focused on how to prevent the body from attacking factor VIII in hemophilia patients and treatment options for when it occurs.
  • NHLBI Expert Panel Report on von Willebrand Disease. In 2008, we published an evidence-based report on the causes, diagnosis, and treatment of von Willebrand disease (VWD). The first report of its kind prepared in the United States, it described initial screening, diagnosis, and management for patients who have the disorder, along with directions for future research.
  • Providing Access to NHLBI Biologic Specimens and Data. The NHLBI’s Biologic Specimen and Data Repository Information Coordinating Center (BioLINCC) centralizes and integrates biospecimens and clinical data that were once stored in separate repositories. BIoLINCC studies included the Multicenter Hemophilia Cohort Studies (MHCS), which enrolled participants who had hemophilia or VWD and developed hepatitis C.

Learn about some of the pioneering research contributions we have made over the years that have improved clinical care.

Advancing research for improved health
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In support of our mission, we are committed to advancing bleeding disorder research in part through the following ways.

  • We perform research. Our Division of Intramural Research, which includes investigators from the Hematology Branch, performs research on bleeding disorders such as those associated with low platelet numbers.
  • We fund research. The research we fund today will help improve our future health. Our Division of Blood Diseases and Resources oversees much of the research on bleeding disorders we fund, helping us to understand and manage the condition. Search the NIH RePORTer to learn about research the NHLBI is funding on blood disorders.
  • We stimulate high-impact research. Our Trans-Omics for Precision Medicine (TOPMed) program includes participants who have bleeding disorders, which may help us understand how genes contribute to differences in disease severity and how patients respond to treatment. The NHLBI Strategic Vision highlights ways we may support research over the next decade.

Learn about exciting research areas the NHLBI is exploring about bleeding disorders.

Participate in NHLBI Clinical Trials

We lead or sponsor many studies on bleeding disorders. See if you or someone you know is eligible to participate in our clinical trials.

Are you an adult who is planning to have a surgical procedure?

This study aims to determine whether providing blood plasma before a surgical procedure can help to reduce bleeding complications in people who have slightly abnormal test results for the prothrombin time (PT) test. To participate in this study, you must be at least 21 years old, have a surgical procedure planned, and not have a bleeding disorder caused by genetics or another disease. This study is located in Baltimore, Maryland, and New Brunswick, New Jersey.

Do you or your child have a platelet, bleeding, or white blood cell disorder?

This study is looking at people who have platelet or other blood disorders. The researchers will use a blood sample to look for problems with platelets and a possible genetic cause in the participant’s DNA or RNA. To participate in this study, you must be a child or adult who either is healthy or has a platelet disorder, coagulation disorder, or white blood cell disorder. This study is located in New York, New York.

More Information

After reading our Bleeding Disorders Health Topic, you may be interested in additional information found in the following resources.

Non-NHLBI resources
- Bleeding Disorders

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