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What is hemophilia? — Hemophilia is a condition that keeps blood from clotting normally. If blood doesn't clot normally, people can bleed very easily or much more than normal. The bleeding can sometimes be life-threatening.
People with hemophilia are missing a protein in the blood called a "clotting factor." Without this, the blood can't clot normally. There are 2 main types of hemophilia (called "A" and "B"), depending on which clotting factor is the problem:
In hemophilia A, factor 8 (also written as "factor VIII") is missing or very low.
In hemophilia B, factor 9 (also written as "factor IX") is missing or very low.
Hemophilia is a life-long condition that a person is born with. It is caused by an abnormal gene. Sometimes, parents pass this abnormal gene to their child. Other times, a child can get hemophilia from a new gene abnormality that happens before they are born. In some of these cases, parents might not know they have the abnormal gene, because they don't have any symptoms. Boys and men are most likely to have hemophilia. It is very rare in girls or women.
Hemophilia can be mild or severe. It can be managed with different treatments.
What are the symptoms of hemophilia? — Symptoms depend on how mild or severe a person's hemophilia is. Some children start having symptoms from birth. For example, a baby boy might bleed much more than normal if he has a procedure to remove the skin that covers the tip of the penis (called "circumcision"). Other children, especially those with mild hemophilia, start having symptoms later on.
People with mild hemophilia usually bleed more than normal after an injury, procedure, or surgery.
People with severe hemophilia also bleed more than normal after an injury, procedure, or surgery. But they can also have bleeding that happens for no reason at all. This type of bleeding usually happens in a joint. The joints most often involved are the ankles, knees, and elbows. Blood in a joint can cause pain, swelling, stiffness, and trouble moving the joint. Over time, repeated bleeding in a joint can lead to long-term joint pain and damage.
Symptoms can also happen from bleeding in other parts of the body. These can include:
Blood in a bowel movement
Blood in the urine
Belly pain (from bleeding into the belly wall)
Bruises or bleeding in a muscle
Bleeding in the brain or spinal cord
Is there a test for hemophilia? — Yes. Your doctor or nurse can check for hemophilia by doing different blood tests.
What if I am pregnant? — Pregnant women who have the hemophilia gene have the chance of passing the gene along to their baby. Genetic testing can show if you have the gene. If you do, doctors can do a few things to help prevent problems:
Do an ultrasound to find out the sex of your baby – This is because only a male baby would be at risk of having severe hemophilia. If the baby is male, doctors will avoid certain procedures during labor and delivery that could cause bleeding. In most cases, the baby is tested after birth to find out if he does have hemophilia.
Prepare for a safe birth – Some women who carry the gene are at risk of abnormal bleeding. Your doctor will test your clotting factor levels. This can help them avoid or prepare for procedures that might cause bleeding. Depending on your levels, you might also need treatment for bleeding after the baby is born.
How is hemophilia treated? — Treatment depends on how severe a person's hemophilia is. It also depends on whether the person is going to have a procedure or surgery.
The main treatment for hemophilia is called "factor replacement therapy." This involves getting the clotting factor that the body is missing. There are different types of replacement clotting factors. Some are made from human blood, and others are made using cells grown in a lab. Replacement therapy goes into a vein. People can get this treatment in the hospital, or they can give it to themselves (or have someone else give it to them) at home.
Replacement therapy is used in 2 ways:
To treat a bleed when it happens
On a regular basis, to prevent bleeding
For people with hemophilia A, another treatment can be used instead of factor replacement. This is a medicine called emicizumab (brand name: Hemlibra). It is given as a shot under the skin once a week, every other week, or once a month.
Deciding which treatment is best can be complicated. Hemophilia treatment centers can help people with hemophilia, and their doctors, decide which treatment is best. These centers also help people plan ahead for things like surgery.
Some people have something called an "inhibitor" in their blood. This can make factor replacement therapy not work as well. This is more common in hemophilia A than in hemophilia B. If tests show that you have an inhibitor, you might need other treatments. Your doctor will talk to you about the options.
What else should I know about replacement therapy? — In the past, factor replacement therapy made from human blood sometimes had viruses in it. This could include HIV (the virus that causes AIDS) and the virus that causes hepatitis C, which could then infect the person being treated for hemophilia. Today, replacement therapy is made in a safer way and does not contain HIV or hepatitis C virus.
What else can people with hemophilia do to avoid bleeding problems? — To avoid bleeding problems, people with hemophilia should:
See their doctor for regular visits
Let every doctor who takes care of them know they have hemophilia, and which type ("A" or "B")
Follow their doctor's instructions about treatment and which activities or sports to avoid (if any)
Learn the signs and symptoms of bleeding, and how to treat it
Not take aspirin or medicines called NSAIDs without the input of a doctor – Common NSAIDs include ibuprofen (sample brand names: Advil, Motrin) and naproxen (sample brand names: Aleve, Naprosyn).
Plan ahead for any procedures or surgery that could cause bleeding
Take good care of their teeth and see their dentist for regular visits
Take their medicines with them when travelling
If your child has hemophilia, you should let caregivers, daycare, or the school know. Teach them which symptoms to watch for, and how to treat a bleed.
How can I learn more about hemophilia? — To learn more, talk with your doctor or nurse. The Hemophilia Foundation also has a lot of information. Their website is Their toll-free phone number in the US is 1-800-424-2634.
All topics are updated as new evidence becomes available and our peer review process is complete.
This topic retrieved from UpToDate on: Mar 30, 2020.
Topic 83610 Version 7.0
Release: 28.2.2 - C28.105
© 2020 UpToDate, Inc. and/or its affiliates. All rights reserved.

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