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What is Chorionic Villus Sampling?

Chorionic Villus Sampling (CVS) is a test that can detect certain problems in a fetus, including genetic conditions and

chromosome problems. CVS is done during early pregnancy, most often between the 10th and 13th weeks.

Chorionic villi are tiny finger-shaped growths found in the placenta. The chorionic villus cells have the same genetic material as the baby’s cells. During CVS, a sample of the chorionic villus cells is taken. The sample is collected by putting a thin tube (catheter) through the vagina, or by inserting a long, thin needle through the belly. Ultrasound is used to guide the catheter or needle to the right location.

CVS can detect many genetic conditions, including Tay-Sachs disease and hemophilia. It can also find chromosome problems, such as down syndrome. CVS does not detect neural tube defects.

CVS is done earlier in pregnancy than amniocentesis (usually done at 15 to 20 weeks), and the results are available sooner. This gives patients more time to make decisions about their pregnancy, or plan for the future.

Watch A Video On CVS  

This informative video features William Goodnight, MD presenting an overview of prenatal evaluations and diagnostic tools.