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 between 15 and 22 weeks. Many people now have NIPT instead, but the AFP part still screens for spina bifida.
Why it's done
- Offered in pregnancy
Getting ready and what happens
- None.
How the test is done
- A health worker cleans the skin, puts a band around your arm, and draws blood from a vein with a small needle. It takes a few minutes.
What the results mean
Screen positive
Means a higher chance, not a diagnosis. Ultrasound, NIPT, or amniocentesis can follow.
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.