What is "chorionic villus sampling"

n. (context medicine English) A form or prenatal diagnosis in which part of the placental tissue is tested for genetic abnormality

n. a prenatal test to detect birth defects at an early stage of pregnancy; tissue from the chorionic villi is assayed [syn: chorionic villus biopsy]

Chorionic villus sampling (CVS), sometimes called "chorionic villous sampling" (as "villous" is the adjectival form of the word "villus"), is a form of prenatal diagnosis to determine chromosomal or genetic disorders in the fetus. It entails sampling of the chorionic villus ( placental tissue) and testing it for chromosomal abnormalities, usually with FISH or PCR. CVS usually takes place at 10–12 weeks' gestation, earlier than amniocentesis or percutaneous umbilical cord blood sampling. It is the preferred technique before 15 weeks.

CVS was performed for the first time by Italian biologist Giuseppe Simoni, scientific director of Biocell Center, in 1983.

Use as early as 8 weeks in special circumstances has been described.

It can be performed in a transcervical or transabdominal manner.

Although this procedure is mostly associated with testing for Down Syndrome, overall, CVS can detect more than 200 disorders.