What is a CVS? How is this relevant to my pregnancy?

July 6, 2019

Chorionic Villus Sampling

Chorionic Villus Sampling (CVS)

Every pregnancy is unique. Some individuals may wish to pursue genetic testing for chromosomal or genetic conditions based on past pregnancy or family history, ultrasound or genetic screening results, or just to gain further information regarding their pregnancy. People may consider diagnostic testing for many reasons, some of which are listed below.

  • Previous pregnancy with genetic or chromosomal condition
  • Pregnancy with high-risk non-invasive prenatal testing or first trimester screening
  • Pregnancy with structural differences on ultrasound 
  • Individuals with a family history of genetic disorders
  • Individuals who are carriers for conditions in which their partner is also a carrier
  • Learning more about their pregnancy

What is this testing? Are there risks? 

Chorionic Villus Sampling (CVS) is a diagnostic procedure in which a sample of placenta is taken. As this is a diagnostic procedure, this provides a yes or no assessment of chromosomal conditions within pregnancy. However, as this is an invasive test, there is a 1-2 in 1,000 chance for miscarriage.

When is this completed?

Chorionic villus sampling can be completed as early as 11 weeks of the pregnancy. This procedure is often not performed after 14 weeks of the pregnancy. 

I am considering a CVS, now what?

Talk to your doctor about it – they may refer you to a maternal fetal medicine specialty clinic for further discussion.

Women who are considering chorionic villus sampling will often meet with a genetic counselor. This allows better understanding of the procedure itself, the risk to the pregnancy, and the multiple types of genetic testing available following receipt of the sample. To learn more about the different types of testing, when to expect these results, and interpretation of these results ask our genetic counselor. They’re here to help you!