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"Are chronic villus tests necessary for pregnant women?"


Is this a necessary procedure? If it isn't what is the harm in skipping it? I don't want to risk anything.


A chorionic villus test is a diagnostic procedure that is performed in order to obtain genetic material from the growing baby that can be used to test for any possible genetic abnormality. The procedure is performed in the first trimester of the pregnancy, and it involves placing an needle into the placenta to remove some cells for analysis (the needle is not placed into the baby). Usually this is done by guiding the needle through the abdominal wall under ultrasound.

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The procedure is not routine for every pregnancy. It tends to be performed when there is a high risk of a genetic problem with the baby. For example, it may be recommended in older mothers (as they have a higher risk of chromosome problems in their eggs) or in those who have already a history of potential genetic problems with other pregnancies or with a family history of genetic problems. If these things do not apply to you, then chorionic villus testing is not even on the table. The risk of chorionic villus testing is loss of the pregnancy, which occurs about 2% of the time. Infection and bleeding are other risks. Therefore, the desire to know if there is a genetic problem must be weighed against this risk.

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