Your health care provider or a genetic counselor will help you understand your chorionic villus sampling results. Occasionally, test results are unclear and amniocentesis — another prenatal diagnostic test — is needed to clarify the diagnosis.

With chorionic villus sampling, there's a rare chance of a false-positive test — when the test is positive, but no disease exists. It's also important to remember that chorionic villus sampling can't identify all birth defects, including spina bifida and other neural tube defects.

If chorionic villus sampling indicates that your baby has a chromosomal or genetic condition that can't be treated, you might be faced with wrenching decisions — such as whether to continue the pregnancy. Seek support from your health care team and your loved ones during this difficult time.

Oct. 10, 2012