If you are a pregnant mom and if the CVS procedure is on your next checklist and wondering who needs CVS, why it is necessary, and the conditions it detects, then this blog is especially for you.

What does CVS detect?

Before getting into what CVS detects, we need to understand a few basics about the CVS procedure.

It is known that the placenta removes waste from the baby’s blood while also supplying oxygen and nutrients to the developing fetus.

A baby’s chromosomal condition, such as Down syndrome, as well as other genetic conditions, like cystic fibrosis, can be detected through chorionic villus sampling. Even though chorionic villus sampling can give you important information about the health of your unborn child, it’s important to be aware of the risks and be ready for the results.

What is the purpose of CVS? Who needs CVS procedure?

A chorionic villus sample can reveal genetic details about your unborn child. Usually, chorionic villus sampling is recommended when the test results could significantly affect how the pregnancy is managed or whether you want to carry the baby to term.

Pregnancy weeks of 11 to 14 are typically ideal to carry out the chorionic villus sampling, which is much earlier than other prenatal diagnostic tests like amniocentesis.

Basically, you will be referred to CVS if:

• Prenatal screening test outcomes were favorable in your case. You may decide to undergo chorionic villus sampling to confirm or rule out a diagnosis if screening test results are positive or concerning, such as those from a first-trimester screen or a prenatal cell-free DNA test.
• You experienced a chromosomal disorder during a prior pregnancy. This pregnancy may also be at a slightly higher risk if a previous pregnancy was impacted by Down syndrome or another chromosomal disorder.
  
• If you were 35 years of age or older. Babies born to mothers 35 years of age and older are more likely to have chromosomal disorders like Down syndrome.
  
• You or your partner are known carriers of a genetic condition, or you have a family history of a particular genetic disorder. Chorionic villus sampling can also be used to diagnose many other genetic disorders, such as Tay-Sachs disease and cystic fibrosis, in addition to Down syndrome.

What conditions does a CVS test for? What abnormalities can CVS detect?

An unborn child can be diagnosed with genetic diseases or chromosome disorders using CVS testing. These consist of

• Down syndrome – a condition that results in various health issues, physical characteristics, and intellectual disabilities.
  
• Cystic fibrosis – a condition that makes breathing difficult due to the accumulation of mucus in the lungs and other organs.
  
• Red blood cell disorder – also called sickle cell disease, may result in discomfort, infections, organ injury, and strokes.
  
• Tay-Sachs disease – a condition that results in the accumulation of fatty proteins in the brain. It has an impact on mental development, hearing, and sight. By the age of five, Tay-Sachs patients typically pass away.
  

Conducted during the 10th and 13th week of pregnancy, the CVS testing can be done and is very accurate. However, it can only identify specific genetic diseases.

A CVS test cannot detect or diagnose birth defects like neural tube defects, which result in abnormal brain and/or spinal development in developing infants. These and other birth defects can be detected or screened for using a variety of tests, such as an AFP blood test.

Is the CVS test necessary?

CVS is not routinely suggested during pregnancy. It is only provided if there is a high likelihood that your baby will have a genetic or chromosomal condition.

Therefore it is crucial to take it up when it comes from a trusted fetal medicine specialist. If you have dicey thoughts in making a decision, take an expert’s help as to what the test entails and inform you of any potential benefits.

Concluding lines

Some chromosome and genetic disorders necessitate extensive medical treatment for your baby. Other disorders may be incurable. If your CVS test results were abnormal, you should consult with your doctor about your options and any decisions you may need to make.
It may also be beneficial to consult with a genetic counselor both before and after receiving your results. A genetic counselor such as the one from Jammi Scans can help you understand your results.

Chennai Women’s Clinic is now Jammi Scans