Chorionic villus sampling is used in pregnancy to obtain fetal cells for genetic testing during which period?

Chorionic villus sampling is used in pregnancy to obtain fetal cells for genetic testing during which period?

• A. First trimester
• B. Second trimester
• C. Third trimester
• D. Postpartum

Answer: (A)

Chorionic villus sampling is an early prenatal diagnostic technique that uses placental tissue, which contains fetal genetic material, to test for chromosomal and genetic anomalies. Because this tissue can be obtained in the first trimester, CVS is done during the early weeks of gestation—typically around 10 to 12 weeks. This allows genetic information to be obtained sooner than amniocentesis, which samples amniotic fluid in the second trimester (about 15–20 weeks). Postpartum and third-trimester testing aren’t used for this purpose, since the procedure is designed for early fetal genetic testing.

Chorionic villus sampling is an early prenatal diagnostic technique that uses placental tissue, which contains fetal genetic material, to test for chromosomal and genetic anomalies. Because this tissue can be obtained in the first trimester, CVS is done during the early weeks of gestation—typically around 10 to 12 weeks. This allows genetic information to be obtained sooner than amniocentesis, which samples amniotic fluid in the second trimester (about 15–20 weeks). Postpartum and third-trimester testing aren’t used for this purpose, since the procedure is designed for early fetal genetic testing.