Good to knowOne result rarely tells the whole story. Your provider looks at your results together with your symptoms, exam, and other tests.
What the test is
It's done 24 to 48 hours after birth, along with hearing and heart (pulse oximetry) checks.
Why it's done
- Every baby born in the U.S.
Getting ready and what happens
- None. Feeding normally helps accuracy.
How the test is done
- The baby's heel is pricked and blood drops are placed on a card.
What the results mean
Out-of-range result
Most out-of-range screens turn out normal on repeat testing, but follow up quickly as directed.
Questions to ask your provider
- What do my results mean for me?
- Do I need to repeat this test or have other tests?
Risks
A blood draw is very safe. You may have slight pain or a small bruise where the needle went in.
Related conditions
Related tests
Sources
Last updated 2026-11-13.