PD_ Fitness and WellBeing_67058 Chorionic villi sampling (CVS) is a procedure performed in the first trimester of pregnancy to detect to detect birth defects by taking a sample of cells from parts of the placenta called the chorionic villi, which have the same genes as the fetus. CVS can detect most of the same defects as amniocentesis, but it cannot detect open neural tube defects. If you have CVS, you will want to consider having a blood alpha-fetoprotein (AFP) test later in your pregnancy to test for neural tube defects.

Here is some information about the test and the risks involved.

Your doctor will discuss the benefits and risks of the test with you based on your particular pregnancy. This test is only useful if the results will change the management of your pregnancy, or change your desire to continue the pregnancy. If you are at higher risk for having a baby with birth defects, you may wish to have this test. Examples of things that may put you at higher risk are:

  • Age 35 years old or older when you give birth.
  • Family history of certain birth defects.
  • Previous child with a birth defect.
  • Abnormal results on other genetic screening tests.