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What is chorionic villus sampling (CVS)?

CVS is a test which tells for sure if your baby has Down syndrome or trisomy 18.

This test is usually done between 11 and 13 weeks of pregnancy.

Using ultrasound, a small piece of tissue is removed from the placenta for testing, usually through the vagina, but sometimes through the abdomen.

Any pregnant person can have a miscarriage at this time of pregnancy.  If a pregnant person has CVS, this chance is increased by an extra 1 in 100 (1%).

The result is available in 2-3 weeks.  Most times, CVS will show that your baby does not have Down syndrome or trisomy 18. CVS can not find every condition. Even after a normal CVS result, there is a chance of having a baby with a different condition such as a hole in the heart or mental disability.  Remember, most babies are born healthy.

For more details, discuss CVS with your health care provider.

CVS is not available in all areas.