When is Chorionic villus sampling (CVS) typically performed during pregnancy?

Chorionic villus sampling (CVS) is a prenatal test that is usually performed between 10 and 12 weeks of gestation. This timing is critical as it allows for the collection of cells from the placenta, which contain the same genetic material as the fetus, to test for chromosomal abnormalities, such as Down syndrome, or other genetic disorders.

Performing CVS too early (before 10 weeks) can increase the risk of complications, such as miscarriage or insufficient sample collection due to the small size of the gestational tissue. Conversely, performing the procedure after 12 weeks can be less advantageous in terms of timing for managing any identified abnormalities before the pregnancy progresses further. Therefore, the 10-12 week window is ideal, allowing for early detection while minimizing risks associated with the procedure. This reasoning confirms why the answer indicating the 10-12 week timeframe is the most appropriate choice for CVS procedures during pregnancy.