What Is Chorionic Villus Sampling?

Baby Talk

Chorionic villus sampling (CVS) is a diagnostic test that can be given as early as the 9th week of pregnancy to identify or rule out certain birth defects.

Chorionic villus sampling (CVS) is a diagnostic test that can identify or rule out certain birth defects. It is similar to an amniocentesis, with one major advantage: It can be done as early as the 9th week of pregnancy. This difference becomes important if the test reports the presence of a birth defect and the parents wish to have an abortion. It is always best to have an abortion as early in the pregnancy as possible.

An amniocentesis is rarely performed before the 12th week, and it can take several more weeks to learn the results. This long wait makes medically necessary abortions much more difficult both emotionally and physically.

CVS is not routinely offered to all pregnant women. Like amniocentesis, it carries the risk of miscarriage and possibly other complications such as limb abnormalities if performed before the 10th week. But it is an option for women who fit into one of these categories:

  • Women over age 35. The risk of bearing a child with certain chromosomal birth defects increases as a woman ages.
  • Women with a history of bearing a child (or children) with a birth defect.
  • Women whose family medical history shows their children may be at risk for inheriting a genetic disorder.
Hey Mom!

When you schedule your CVS test, plan to take the rest of the day off. It can be emotionally and physically tiring. This is a great excuse to take a day for yourself.

CVS is generally performed in a hospital. Like an amniocentesis, ultrasound monitoring picks up the location and position of the fetus and placenta. A catheter (a small tube that's attached to a syringe) is used to extract the needed cells, but instead of taking amniotic fluid, the doctor will take a sampling of cells from the placenta.

The entry is first swabbed with an antiseptic solution to prevent infection. Then the doctor inserts either a catheter into the vagina through the cervix, or a needle through the abdomen, in order to obtain a tiny piece of chorionic villi (fetal cells of the placenta) for analysis. No anesthetic is given because this test is not painful. However, some women say they feel a pinch when the sample is taken.

After amniocentesis, you may feel some cramping and have some spotting, but this should stop within a few days.


excerpted from:

Excerpted from The Complete Idiot's Guide to Pregnancy and Childbirth © 2004 by Michele Isaac Gliksman, M.D. and Theresa Foy DiGeronimo. All rights reserved including the right of reproduction in whole or in part in any form. Used by arrangement with Alpha Books, a member of Penguin Group (USA) Inc.

To order this book visit Amazon's website or call 1-800-253-6476.

Pregnancy Day by Day

Tell us your due date to receive our daily newsletter and find out what is happening in this day of your pregnancy!

Already a member? Log-in here

Name of the Day


Vote Now for the Children's & Teen Choice Book Awards
Voting is open now through May 3 for the Children's and Teen Choice Book Awards — the only national book awards program where the winning author, illustrator, and books of the year are selected by young readers. Encourage your child to vote for his favorites today!

Find Today's Newest & Best Children's Books!
Looking for newly released books for your child? Try our new Book Finder tool to search for new books by age, type, and theme, and create reading lists for kids!

Top 10 Math & Science Apps for Your Whiz Kid
Looking for the best math and science apps for kids? Check out these cool apps for all ages, which will grow your child's love of the STEM subjects (science, technology, engineering, and math).

Registered for Kindergarten — Now What?
Wondering what to do now that you've signed your child up for kindergarten? Try our award-winning Kindergarten Readiness app! This easy-to-use checklist comes with games and activities to help your child build essential skills for kindergarten. Download the Kindergarten Readiness app today!

stay connected

Sign up for our free email newsletters and receive the latest advice and information on all things parenting.

Enter your email address to sign up or manage your account.

Facebook icon Facebook icon Follow Us on Pinterest

© 2000-2015 Pearson Education, Inc. All Rights Reserved.