Hemophilia screening
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Hemophilia Microchapters |
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Diagnosis |
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Treatment |
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Case Studies |
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Hemophilia screening On the Web |
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American Roentgen Ray Society Images of Hemophilia screening |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Simrat Sarai, M.D. [2]
Overview
There is currently no screening program indicated for individuals in unaffected families but in hemophilia carrier families considering their first or subsequent child benefit enormously from genetic counseling. Genetic counselors provide information and support for carriers and their families, before they conceive a child, and after the unpredicted birth of a son with hemophilia.
Screening
Haemophilia can be diagnosed before, during or after birth if there's a family history of the condition. Several options are available to parents.
If there's no family history of haemophilia, it's usually only diagnosed when a child begins to walk or crawl. They may experience joint bleeds or easy bruising. Mild haemophilia may only be discovered later, usually after an injury or a dental or surgical procedure.
Tests before pregnancy
Genetic testing and counselling are available to help determine the risk of passing the condition onto a child. This may involve testing a sample of your tissue or blood to look for signs of the genetic mutation that causes haemophilia.
Tests during pregnancy
If you become pregnant and have a history of haemophilia in your family, tests for the haemophilia gene can be carried out. These include:
- chorionic villus sampling (CVS) – a small sample of the placenta is removed from the womb and tested for the haemophilia gene, usually during weeks 11-14 of pregnancy
- amniocentesis – a sample of amniotic fluid is taken for testing, usually during weeks 15-20 of pregnancy.
- PUBS (percutaneous umbilical blood sampling)- PUBS directly tests the blood of the unborn baby. It is done after the 20th week of pregnancy. The doctor takes blood from the umbilical vein which runs from the baby to the placenta. The test results are ready in just a few days.
There's a small risk of these procedures causing problems such as miscarriage or premature labour, so you may want to discuss this with the doctor in charge of your care.
Tests after birth
If haemophilia is suspected after your child has been born, a blood testcan usually confirm the diagnosis. Blood from the umbilical cord can be tested at birth if there's a family history of haemophilia. A blood test will also be able to identify whether your child has haemophilia A or B, and how severe it is. [1]