Chorionic villus sampling involves removing a portion of which tissue?

Chorionic villus sampling involves removing a portion of which tissue?

• A. Placenta
• B. Amniotic fluid
• C. Umbilical cord
• D. Fetus

Answer: (A)

Chorionic villus sampling targets tissue from the placenta, specifically the chorionic villi, which contain fetal DNA. These villi are part of the developing placenta and form early, making CVS usable around 10–13 weeks of gestation for genetic testing. This is different from other prenatal tests that sample other tissues: amniocentesis collects amniotic fluid, not placental tissue; cordocentesis samples fetal blood from the umbilical cord; and sampling the fetus itself isn’t how CVS is performed. Because the tissue comes from the placenta and carries fetal genetic material, CVS provides an early window into fetal genetics.

Chorionic villus sampling targets tissue from the placenta, specifically the chorionic villi, which contain fetal DNA. These villi are part of the developing placenta and form early, making CVS usable around 10–13 weeks of gestation for genetic testing. This is different from other prenatal tests that sample other tissues: amniocentesis collects amniotic fluid, not placental tissue; cordocentesis samples fetal blood from the umbilical cord; and sampling the fetus itself isn’t how CVS is performed. Because the tissue comes from the placenta and carries fetal genetic material, CVS provides an early window into fetal genetics.