DefinitionBy Mayo Clinic Staff
Chorionic villus sampling (CVS) is a prenatal test in which a sample of chorionic villi is removed from the placenta for testing. The sample can be taken through the cervix (transcervical) or the abdominal wall (transabdominal).
During pregnancy, the placenta provides oxygen and nutrients to the growing baby and removes waste products from the baby's blood. The chorionic villi are wispy projections of placental tissue that share the baby's genetic makeup.
Chorionic villus sampling is usually done between weeks 10 and 13 of pregnancy — earlier than other prenatal diagnostic tests, such as amniocentesis. Chorionic villus sampling can reveal whether a baby has a chromosomal condition, such as Down syndrome. Chorionic villus sampling can also be used to test for other genetic conditions, such as cystic fibrosis.
Although chorionic villus sampling can provide valuable information about your baby's health, it's important to understand the risks — and be prepared for the results.
Oct. 17, 2015
- Ghidini A. Chorionic villus sampling. http://www.uptodate.com/home. Accessed Aug. 4, 2015.
- Frequently asked questions. Pregnancy FAQ164. Diagnostic tests for birth defects. American College of Obstetrics and Gynecology. http://www.acog.org/Patients/FAQs/Diagnostic-Tests-for-Birth-Defects. Accessed July 31, 2015.
- Cunningham FG, et al. Prenatal diagnosis. In: Williams Obstetrics. 24th ed. New York, N.Y.: The McGraw-Hill Companies; 2014. http://www.accessmedicine.com. Accessed Aug. 3, 2015.
- Gabbe SG, et al. Prenatal genetic diagnosis. In: Obstetrics: Normal and Problem Pregnancies. 6th ed. Philadelphia, Pa.: Saunders Elsevier; 2012. http://www.clinicalkey.com. Accessed Aug. 3, 2015.
- Frequently asked questions. Pregnancy FAQ027. The Rh factor: How it can affect your pregnancy. American College of Obstetrics and Gynecology. http://www.acog.org/Patients/FAQs/The-Rh-Factor-How-It-Can-Affect-Your-Pregnancy. Accessed July 31, 2015.
- Frequently asked questions. Pregnancy FAQ171. Cystic fibrosis: Prenatal screening and diagnosis. American College of Obstetrics and Gynecology. http://www.acog.org/Patients/FAQs/Cystic-Fibrosis-Prenatal-Screening-and-Diagnosis. Accessed July 31, 2015.
- American College of Obstetricians and Gynecologists (ACOG) Committee on Practice Bulletins — Obstetrics. ACOG Practice Bulletin No. 88: Invasive Prenatal Testing for Aneuploidy. Obstetrics and Gynecology. 2007;110:1459.
- Gibbs RS, et al. Prenatal diagnosis. In: Danforth's Obstetrics and Gynecology. 10th ed. Philadelphia, Pa.: Wolters Kluwer Health Lippincott Williams & Wilkins; 2008. http://www.danforthsobgyn.com. Accessed Aug. 3, 2015.
- American College of Obstetricians and Gynecologists. Birth defects. In: Your Pregnancy and Childbirth Month to Month. 5th ed. Washington, D.C.: American College of Obstetricians and Gynecologists; 2010:343.
- Patient information: Chorionic villus sampling. http://www.uptodate.com/home. Accessed Aug. 4, 2015.
- Beckman CRB, et al. Genetics and genetic disorders in obstetrics and gynecology. In: Obstetrics and Gynecology. 7th ed. Baltimore, Md.: Lippincott Williams & Wilkins; 2014.
- Vincent Corbett J, et al. Diagnostic procedures related to childbearing years. Laboratory Tests and Diagnostic Procedures with Nursing Diagnoses. 8th ed. Upper Saddle River, N.J.: Pearson Education, Inc.; 2013.
- Fischbach FT, et al. Prenatal diagnosis and tests of fetal well-being. In: A Manual of Laboratory and Diagnostic Tests. 9th ed. Philadelphia, Pa.: Lippincott Williams & Wilkins; 2014.
- Pagana KD, et al. Maternal/Fetal evaluation. In: Mosby's Manual of Diagnostic and Laboratory Tests. 5th ed. St. Louis, Mo.: Elsevier Mosby; 2014.
- Society for Maternal-Fetal Medicine. SMFM Consult: Risks of chorionic villus sampling and amniocentesis. Contemporary OB/GYN. 2014; 59; e.1. http://contemporaryobgyn.modernmedicine.com/contemporary-obgyn/news/RC/smfm-consult-risks-chorionic-villus-sampling-and-amniocentesis. Accessed October 13, 2015.