How is chorionic villus sampling performed?
CVS may be offered to women who are at increased risk for chromosomal abnormalities or have a family history of a genetic defect that is testable from the placental tissue. CVS is usually performed between the 10th and 12th weeks of pregnancy. Although exact methods can vary, the procedure involves inserting a small tube called a catheter through a woman’s vagina and into her cervix and usually follows this process: • Ultrasound is used to guide the catheter into place near the placenta. • Tissue is removed using a syringe on the other end of the catheter. • Another method is transabdominal CVS, which involves inserting a needle through the woman’s abdomen and into her uterus to sample the placental cells. • Women may feel some cramping during and after the CVS procedure. • The tissue samples are sent to a genetic laboratory to grow and be analyzed. Results are usually available in about 10 days to two weeks, depending on the laboratory. Women with twins or other multiples usually need
