Chorionic Villus Sampling (CVS)
Chorionic villus sampling (CVS) is a test performed at approximately 10 to 12 weeks of pregnancy to determine whether the baby has certain genetic defects. It is often used when the mother is over the age of 35, since the risk of abnormalities increases at that point, or if any inheritable conditions run in either of the parents' families.
The chorionic villus is placenta tissue. A small sampling is removed for biopsy in this type of screening, taken either through the cervix or the abdomen. Your doctor will carefully collect the sample from the placenta. Most patients report some discomfort and pressure, but the procedure only takes a few minutes.
While CVS is a common form of testing considered safe when administered by an experienced physician, it is associated with some risks. Potential complications of CVS may include miscarriage, bleeding, infection, membrane rupture and Rh incompatibility in the mother.
A laboratory will assess the CVS sample for any indications of abnormalities in the DNA or chromosomes. The results are typically ready in two weeks. CVS testing can detect the presence of more than 200 conditions, including:
- Down syndrome
- Cystic fibrosis
- Sickle cell anemia
- Tay-Sachs disease
- Duchenne's muscular dystrophy
- Trisomy 13
- Trisomy 18
- Turner syndrome
- Klinefelter syndrome