Hemophilia C: Understanding Factor XI Deficiency
Updated: 2 days ago
Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 2026
Quick Answer
Hemophilia C is an inherited condition in which the body does not make enough factor XI, a protein the blood needs to form clots [1]. It is more common in people of Ashkenazi Jewish descent [1] [2]. While it is generally less severe than other forms of hemophilia, it can lead to significant bleeding during medical procedures or after trauma [1].
What the research says
Factor XI deficiency is more common than older texts suggest, and the bleeding is usually mild. A review of laboratory and molecular diagnosis reports a prevalence of about 1 per 10,000 to 20,000 people in the general population and about 1 in 20 among Ashkenazi Jews. It typically presents as a mild bleeding disorder linked to bleeding after injury or surgery, and it is often discovered when a routine blood test shows a prolonged activated partial thromboplastin time (aPTT) (Davidson & Gomez, Seminars in Thrombosis and Hemostasis, 2025) [2].
Your factor XI level does not reliably predict how much you will bleed. In a cohort of 41 people with factor XI deficiency in Southeast China, 39 had severe deficiency, yet only 9 had mild bleeding, and there was no correlation between factor XI activity and bleeding severity (Zhang et al., Orphanet Journal of Rare Diseases, 2024) [3].
Plasma treatment can, rarely, trigger inhibitors. In a single-center review of 682 patients with factor XI deficiency, inhibitors developed in 7 patients, all with severe deficiency and after exposure to plasma or factor XI concentrate. The bleeding pattern did not change, and later surgeries were managed with low-dose recombinant factor VIIa with good control of bleeding (Kamel et al., Haemophilia, 2024) [4].
Key Takeaways
Feature | Hemophilia C Details |
Alternative Names | Factor XI deficiency, Rosenthal syndrome (Rosenthal disease) [1] |
Deficient Protein | Factor XI (clotting factor 11) |
Inheritance | |
Common Symptoms | Nosebleeds, easy bruising, heavy periods, and prolonged bleeding after surgery or dental work [1] |
Prevalence | |
Primary Treatment |
Understanding the Basics of Hemophilia C
Hemophilia C is a rare, inherited condition that causes a deficiency of clotting factor XI [1]. Clotting factors are proteins in the blood that work together to form a stable clot when a blood vessel is damaged. Without enough factor XI, the clotting process is slower, which can lead to prolonged bleeding.
Hemophilia A (factor VIII deficiency) and hemophilia B (factor IX deficiency) are X-linked and mainly affect males. Hemophilia C is carried on an autosome (a non-sex chromosome), so males and females are affected equally [1]. People with hemophilia C also do not typically have the bleeding into joints and muscles that is seen in hemophilia A and B [1].
Signs and Symptoms
The symptoms of hemophilia C are often mild and may go unnoticed until a person has surgery, dental work, or a serious injury [1]. Spontaneous bleeding, which is common in severe hemophilia A or B, does not usually happen in hemophilia C [1].
Common signs include:
Frequent nosebleeds (epistaxis) [1]: Recurrent bleeding from the nose that may be hard to stop.
Easy bruising: Bruises that appear after a minor bump, including painful, swollen bruises after surgery [1].
Heavy menstrual bleeding: Unusually heavy or long-lasting periods [1].
Prolonged bleeding after procedures: Extended bleeding after a tooth extraction, tonsil removal, or other surgery [1].
Blood in the urine and bleeding after circumcision [1]: Less common, but recognized signs.
Bleeding after childbirth: A higher chance of prolonged or heavy bleeding when giving birth [1].
Causes and Risk Factors
Hemophilia C is caused by changes (mutations) in the F11 gene, which carries the instructions for making factor XI [1]. Because the condition is autosomal recessive, a person typically inherits one mutated copy from each parent [1] to have the more severe form. People who inherit only one copy are carriers, and they usually do not have significant bleeding symptoms [1].
When both parents carry one mutated copy, each child has a 25% chance of having hemophilia C, a 50% chance of being a carrier, and a 25% chance of inheriting two normal copies [1].
Hemophilia C is more common in people of Ashkenazi Jewish descent [1] [2]. One review estimates the frequency of factor XI deficiency in this population at about 1 in 20 [2], and notes that just two gene variants account for most cases in Jewish and Arab populations [2].
Diagnosis and Testing
Diagnosis usually begins with a review of your personal and family history and a physical exam, followed by blood tests [1].
Coagulation screening: An activated partial thromboplastin time (aPTT) test measures how long your blood takes to clot and is often prolonged [1] [2].
Factor XI assay: A clotting factor test that measures how active factor XI is in your blood [1].
Other tests: Providers may also order a complete blood count, a prothrombin time (PT) test, or a fibrinogen test [1], and genetic testing can identify the exact mutation [2] and help with family planning.
Hemophilia C can be hard to diagnose because factor XI levels do not always match symptoms [1] [2] [3]. Some people have a very low level and no bleeding, while others bleed even though their level is close to normal [1].
Treatment and Management
Many people with hemophilia C need treatment only when they bleed or before a planned surgery or procedure [1].
Treatment Type | Description |
Fresh Frozen Plasma (FFP) | Donated plasma that replaces missing clotting factors [1]. It is the most common treatment in many regions. |
Factor XI Concentrates | Purified factor XI, available in some countries for more targeted therapy. |
Antifibrinolytics | Medicines such as tranexamic acid that keep clots from breaking down [1], which is especially useful for dental work. |
Fibrin Glue | A topical agent used to help stop bleeding at a specific site during surgery. |
Hormonal Treatment | Birth control pills may be prescribed for unusually heavy or long-lasting periods [1]. |
Conclusion
Hemophilia C is a rare and usually mild bleeding disorder. It lacks the spontaneous bleeding of other hemophilia types, but it needs careful coordination with your healthcare providers before surgery, dental work, or childbirth. With a proper diagnosis and a proactive plan, most people with hemophilia C live full and active lives.
Frequently Asked Questions
Is hemophilia C the same as hemophilia A?
No. Hemophilia A is a deficiency of factor VIII, while hemophilia C is a deficiency of factor XI.
Can women get hemophilia C?
Yes. Unlike hemophilia A and B, hemophilia C affects men and women equally [1].
What is the most common symptom?
Prolonged bleeding after surgery or dental work is the most common sign [1].
Is there a cure for hemophilia C?
There is currently no cure, but it is manageable with proper treatment.
How is it inherited?
It is inherited in an autosomal recessive pattern [2].
What is Rosenthal syndrome?
It is another name for hemophilia C (also called Rosenthal disease) [1]. It was first described in 1953 by Rosenthal and colleagues (Rosenthal et al., 1953) [5].
Are spontaneous joint bleeds common?
No. People with hemophilia C do not typically have the joint and muscle bleeding seen in hemophilia A or B [1].
Do all people with the gene have symptoms?
No. Many carriers with one mutated gene have no symptoms at all [1].
Is hemophilia C life-threatening?
It is usually mild, but severe bleeding after major trauma or surgery can be life-threatening if it is not managed [1].
What population is most at risk?
Can it be diagnosed at birth?
Genetic testing can identify it at any age, including in newborns when there is a known family history. Ask your hematologist how and when to test.
What is a factor XI assay?
A blood test that measures the activity level of clotting factor XI.
Are there special precautions for dental work?
Yes. Tell your dentist about your condition. You may need an antifibrinolytic medicine such as tranexamic acid, and sometimes plasma [1], so plan ahead with your hematologist.
Does exercise help?
General fitness is good, but talk to your hematologist about contact sports.
Can I take aspirin?
Aspirin and other NSAIDs can increase bleeding, so ask your hematologist before taking them.
What is FFP?
Fresh frozen plasma, which is used to replace missing clotting factors [1].
Are factor XI concentrates available everywhere?
No. They are only available in certain countries.
Is it related to vitamin K?
No. Factor XI deficiency is genetic and is not related to vitamin K levels.
Can I have a normal pregnancy?
Yes, but bleeding after childbirth is a concern [1], so you need close planning with a hematologist and an obstetrician.
What is tranexamic acid?
An antifibrinolytic medicine that helps keep blood clots from breaking down.
Is hemophilia C common?
No. It is considered a rare disease [1].
Can stress cause bleeding?
Stress does not directly cause bleeding in hemophilia C.
What should I do in an emergency?
Carry a medical alert card that identifies your condition, and tell the care team about it right away.
Are there support groups?
Yes. Organizations such as the National Hemophilia Foundation provide resources.
Does the severity change over time?
Factor XI levels are usually stable throughout life, although bleeding risk does not always follow the level [2] [3].
Can I travel safely?
Yes, but you should know where the nearest hemophilia treatment center is.
What is a "carrier"?
Someone who has one mutated gene and usually no symptoms [1].
Is genetic counseling recommended?
Yes, for families with a history of the condition.
What is a prolonged aPTT?
A lab result showing that blood takes longer than normal to clot.
Can I get tattoos?
Tattoos involve needles and can cause bleeding, so consult your doctor first.
Is hemophilia C painful?
The condition itself is not painful, but bleeding into tissues can cause pain.
Can it cause internal bleeding?
It can, but usually only after a significant injury or surgery [1].
Are there dietary restrictions?
No specific diet is required, but overall health is important.
Can I give blood?
Eligibility depends on the blood center and your situation, so ask your hematologist and the blood center before donating.
What is a hematologist?
A doctor who specializes in blood disorders.
Is hemophilia C more common in children?
It is present from birth because it is genetic, but symptoms often do not appear until adulthood [1].
Can I take Tylenol?
Acetaminophen (Tylenol) is usually used for pain relief in people with bleeding disorders. Ask your provider first.
What is an autosome?
Any chromosome that is not a sex chromosome.
How many copies of the gene are needed for symptoms?
Usually two for significant symptoms [1], though some people with one copy have mild bleeding.
Is it contagious?
No. It is a genetic condition and cannot be caught from others.
What is the "clotting cascade"?
A series of steps the blood takes to form a clot.
Where does factor XI fit in the cascade?
It is part of the intrinsic pathway of coagulation.
Can surgery be performed safely?
Yes, with a proper plan before the operation, which may include plasma, factor concentrate, antifibrinolytics, or topical agents.
Are nosebleeds always serious?
Not always, but they should be monitored if they last a long time.
What is a medical alert bracelet?
A piece of jewelry that tells emergency responders about your bleeding disorder.
Can hemophilia C be prevented?
No, because it is inherited [1], but bleeding can be managed.
Does it affect life expectancy?
Most people have mild symptoms [1] and can lead full lives with proper care. Your hematologist can discuss your individual outlook.
What is desmopressin (DDAVP)?
A medicine used in some other bleeding disorders. It is not typically relied on in hemophilia C, so ask your hematologist.
Can I play sports?
Low-impact sports such as swimming are usually recommended.
Who discovered hemophilia C?
It was first described in 1953 by R. L. Rosenthal and colleagues, who reported a hemophilia-like disease caused by deficiency of a third plasma thromboplastin factor [5].
Related Reading
Hemophilia: Symptoms, Causes, Diagnosis & Treatment Guide gives an overview of hemophilia types, symptoms and treatment.
Hemophilia A: Understanding Factor VIII Deficiency and Treatment explains the most common type of hemophilia.
Hemophilia B: Understanding Factor IX Deficiency and Treatment explains factor IX deficiency and how it is treated.
What Is von Willebrand Disease? A Plain-Language Guide to the Lifelong Bleeding Condition You're Usually Born With covers the most common inherited bleeding disorder.
References
Cleveland Clinic. Hemophilia C (Factor XI Deficiency). Cleveland Clinic. Last updated June 28, 2022. https://my.clevelandclinic.org/health/diseases/23337-hemophilia-c
Davidson S, Gomez K. Laboratory and molecular diagnosis of factor XI deficiency. Seminars in Thrombosis and Hemostasis. 2025;51(2):145-154. PMID 39496302. https://doi.org/10.1055/s-0044-1792033
Zhang K, Qin L, Xu F, et al. The spectrum of factor XI deficiency in Southeast China: four recurrent variants can explain most of the deficiencies. Orphanet Journal of Rare Diseases. 2024;19(1):224. PMID 38835089. https://doi.org/10.1186/s13023-024-03235-5
Kamel KS, Riddell A, Jradeh B, et al. Diagnosis and management of factor XI alloinhibitors in patients with congenital factor XI deficiency: a large single-centre experience. Haemophilia. 2024;30(5):1155-1163. PMID 39039722. https://doi.org/10.1111/hae.15081
Rosenthal RL, Dreskin OH, Rosenthal N. New hemophilia-like disease caused by deficiency of a third plasma thromboplastin factor. Proceedings of the Society for Experimental Biology and Medicine. 1953;82(1):171-174. PMID 13037836. https://doi.org/10.3181/00379727-82-20057
Disclaimer
This article is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare professional for diagnosis and treatment.
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