What is Intact Human Chorionic

Definition: Also called intact chorionic villus sampling, this prenatal test involves taking a sample of the chorion, the tissue surrounding the embryo, for genetic testing.

Procedure: It is performed between the 10th and 12th week of gestation. A small part of the chorion at the base of the placenta is removed for analysis. This is usually done through the cervix or via the abdomen by the use of a needle-tipped syringe; both methods use ultrasound to guide the needle to the placenta.

Risks of the procedure: Slight risk of miscarriage