In-Depth
Down syndrome
Tests and diagnosis
- Prenatal testing: Your guide to common tests Prenatal testing — Understand the most common prenatal screening and diagnostic tests.
- Genetic testing Genetic testing — Overview covers why genetic testing is done, preparation and results.
- Cordocentesis Cordocentesis — Overview covers definition, risks, results of this prenatal diagnostic test.
- First trimester screening First trimester screening — Overview covers definition, risks, results of this early prenatal screening test.
- Quad screen Quad screen — Overview covers definition, risks, results of this second trimester prenatal screening test.
- Chorionic villus sampling Chorionic villus sampling — Overview covers definition, risks, results of this early prenatal test.

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