Final answer:
Chorionic villus sampling can be done at around 10 to 13 weeks of pregnancy for genetic testing.
Step-by-step explanation:
Chorionic villus sampling (CVS) can be done at around 10 to 13 weeks of pregnancy. CVS involves the extraction of a small sample of the placenta, specifically the chorionic villi, for genetic testing. This procedure is typically performed earlier in pregnancy compared to amniocentesis, which is usually done around 15 to 20 weeks. However, the specific timing of CVS can vary depending on the healthcare provider and individual circumstances.