Learn what is Chorionic Villus Sampling (CVS) and all about the Purpose, Procedure, Risks & Results associated with it  

Chorionic Villus Sampling (CVS): Why and How is it conducted during Pregnancy and Does it involve any Risks?

Chorionic Villus Sampling or a CVS Test is a prenatal test to detect any genetic disease, birth defects or any other issues related to pregnancy. It is usually conducted between the 10th to 12th week of the gestation period.
The CVS Test procedure

In case of a CVS Test, a tiny bit of the Chorionic villi is drawn out from the placenta which is attached to the uterus wall. The sample is taken from such a location as they possess the same genes which will be present in the new born. It is the reason they are considered the best sample to ascertain the presence of any disease or birth defect in the baby.

Diseases which can be detected

The CVS test can help in timely and accurate detection of the following diseases -

• Genetic diseases such as sickle cell anaemia, Tay-Sachs disease, cystic fibrosis

• Chromosome disorders, for example Down syndrome

• Muscular atrophy common in the male child

Who can have the CVS test done?

Doctors advise the CVS test for women who are at a greater risk of developing genetic defects and disorders which include -

• Presence of a chromosomal abnormality

• A family history of birth defects

• A pregnant woman who is 35 or older, as the chance of risk increases with the age

• A pregnant woman with abnormal results in case of genetic tests.

Pros and Cons of the CVS Test

Pros:

• During the early stage of pregnancy, timely action can be taken to manage any birth defects.

• The termination of pregnancy on receipt of abnormal test results as a safer option as it can be done during the early pregnancy stage

• The test results are available within a period of 10 days to allow for timely decision

Cons:

• The test carriers a higher threat of miscarriage when compared to amniocentesis, a similar prenatal test done from removing amniotic fluid around the sac surrounding the foetus.

• The risk of infection caused is higher at this stage.

Getting ready for the test

When someone is recommended the CVS test, a proper guidance is required to be provided by the doctor related to the advantages and disadvantages of the test. The test takes around 30 minutes to be performed and can be best performed between 10-12 weeks from the last menstrual period.