You may decide not to have birth defects tests because:

• You would continue the pregnancy no matter what the tests show.
• The screening test may be positive even though your baby does not have a problem. You would be worried while you wait for the test results.
• These tests cannot find all possible problems.
• Of a risk of miscarriage. Both CVS and amniocentesis have a small risk of miscarriage. In one study of highly trained providers, the risk from amniocentesis and from CVS was about 1 in 400.² Other studies have shown higher risks, between 2 and 4 in 400.⁵ This greater risk may be more likely in medical centers with less experienced providers, especially for CVS.
• Tests can be expensive. You may not have insurance, or your insurance may not pay for the tests.