Diagnosis & Imaging
Chorionic villus sampling (CVS)
Chorionic villus sampling is a test that samples placental tissue early in pregnancy for genetic information.
In short: Chorionic villus sampling (CVS)
- It can provide genetic information earlier than amniocentesis.
- It samples tissue from the placenta.
- It carries a small procedure-related risk.
- It is one option for prenatal genetic testing.
What it is
It is a procedure in which a small sample of placental tissue (chorionic villi) is collected for genetic testing. It is typically performed earlier in pregnancy than amniocentesis.
Understanding Chorionic villus sampling (CVS)
When genetic information is desired, CVS offers an option earlier in pregnancy than amniocentesis, which some families prefer for earlier results. Like amniocentesis, it carries a small procedure-related risk that the team discusses. CVS samples placental tissue rather than amniotic fluid, but both can provide genetic testing such as a karyotype or microarray when a syndrome is being considered.
Why it matters
Understanding CVS helps families see the options for prenatal genetic testing and the trade-offs of timing and risk, so they can make an informed decision with their team.
Common questions
What does CVS sample?
Placental tissue.
How is it different from amniocentesis?
CVS is done earlier and samples the placenta.
Does it carry risk?
It carries a small procedure-related risk.
Bottom line
Chorionic villus sampling tests placental tissue for genetic information earlier in pregnancy than amniocentesis.
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