What is the difference between a prenatal screening test and a prenatal diagnostic test?
Prenatal screening tests can provide people with information about the likelihood for certain birth defects and/or chromosomal abnormalities in their baby. These tests typically involve blood draws and/or ultrasounds during pregnancy. There are no major risks to the mother or baby with a screening test. These tests do not provide definitive results. Prenatal diagnostic tests include chorionic villus sampling (CVS) and amniocentesis. They can provide definitive information about the baby’s chromosomes and/or other genetic conditions. These tests involve inserting a thin needle through the woman’s abdomen. In some instances, CVS may involve inserting a catheter through the woman’s cervix. These tests have some risks, the most significant of which is miscarriage.
