Diagnosis

Prenatal Testing

If hemophilia has been seen in someone's family history, that person may want to take one of the two prenatal tests that determine whether or not their baby has this bleeding disorder. However, a mother should only undergo these tests if they are considering abortion. Otherwise, one should just wait until after birth to get tested. The two available prenatal tests are chorionic villous sampling and amniocentesis.

Chorionic villous sampling (CVS for short) is a prenatal test where a small piece of tissue is taken from outside of the sac where the fetus develops. This test is taken 10-12 weeks into pregnancy (the testing period is very conflicting among different resources), which is a little earlier than the testing time for amniocentesis. The results from this test come back in approximately 2-4 weeks, revealing the baby' gender and whether or not it has hemophilia. This method is quite safe with a 1% chance of miscarriage.

Picture of CVS:

This is a diagram of how chorionic villous sampling (CVS) is conducted

Amniocentesis is another prenatal test which allows mothers to find out whether their child has some genetic mutation or chromosomal disorder (in this case it would be Hemophilia A). This is the most common method of prenatal testing for genetic diseases, and is taken around 15-18 weeks into pregnancy. This technique determines the fetus's gender and genetic condition. Amniocentesis is also rather safe with a 0.5% chance of miscarriage.

Picture of amniocentesis:

This is a diagram of how amniocentesis is conducted. The round object on top of the woman's stomach is an ultrasound transducer.

 

Testing after Birth

Testing for Hemophilia A after birth is relatively simple. A person who suspects that their child has this disorder can have the child's blood analyzed in an assay. An assay is a test where your blood is examined. This test is conducted to compare the patient's Factor VIII percentage with the normal value of Factor VIII concentration. Another option to test for hemophilia is the bleeding test . Under very carefully controlled conditions, a doctor times the patient on how quickly it takes for their blood to clot. Both of these options can determine whether or not someone has Hemophilia A and it can also determine the patient's severity. These tests are almost always performed on children due to a hemophiliac history or early experiences of excessive bleeding.

 

Sources for this page:

•  "Bleeding Disorders, Factor Deficencies." Canadian Hemophilia Society. 2006. Canadian Hemophilia Society. 21 Nov 2006 < http://www.hemophilia.ca. >

•  Wilson, Jennifer F., MS. "Hemophilia." Gale Encyclopedia of Medicine . Ed. Jacqueline L. Longe. 3rd ed. Detroit : Thomson Gale, 2006. Science Resource Center . Thomson Gale. 28 November 2006 < http://galenet.galegroup.com/servlet/SciRC?ste=1&docNum=CV2642413054 >.

•  "Chorionic Villus Sampling and Amniocentesis: Recommendations for Prenatal Counseling ." CDC: Center for Disease Control . 07/21/1995 . CDC: Center for Disease Control. 15 Jan 2007 <http://wonder.cdc.gov/wonder/prevguid/m0038393/m0038393.asp>.