Prenatal Alpha-Fetoprotein (AFP) with Fetal Nuchal Translucency Screening (for gestational age assessment)
This test measures Alpha-Fetoprotein levels in your blood and evaluates fetal nuchal translucency during early pregnancy to help assess risks for certain birth defects and chromosomal conditions.
["Early pregnancy screening for genetic and structural risks using blood tests and ultrasound."]
Key facts at a glance
- LOINC
- 88004-7
- Short code
- Ts 18 risk-age+PAPPA+HCG+NT Fetus
- Synonyms
- Ts 18 risk-age+PAPPA+HCG+NT Fetus
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 0
- Ref high
- 5
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84702
- SNOMED
- 275917004
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What Is Alpha-Fetoprotein (AFP)?
Alpha-fetoprotein (AFP) is a protein produced mainly by the fetal liver and yolk sac. In your blood, it helps detect potential issues like neural tube defects (e.g., spina bifida) or other chromosomal abnormalities. This test is part of routine prenatal screening.
Why Is This Test Done?
Your healthcare provider may recommend this test between 10 to 14 weeks of pregnancy to screen for conditions that may affect your baby’s health. The fetal nuchal translucency measurement checks the fluid-filled area at the back of the baby’s neck, which can indicate chromosomal risks.
How Is the Test Performed?
A blood sample is taken from your arm, and an ultrasound may be performed to measure the fetal nuchal translucency. Results are analyzed together to assess risk levels.
What Do the Results Mean?
Results are not definitive for diagnosing conditions but provide screening information. A higher-than-expected AFP level or an enlarged nuchal translucency may signal increased risk, prompting further testing (e.g., amniocentesis or chorionic villus sampling).
Reference range
Non-pregnant: <5 mIU/mLN/A
No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test is primarily a screening tool—not a diagnostic test—to identify potential risks for chromosomal abnormalities (e.g., Down syndrome) or neural tube defects. It helps guide decisions about additional testing if needed, ensuring personalized prenatal care.
Short name
AFP + NT Screening
Frequently asked questions
What does an elevated AFP level mean?
Why is fetal nuchal translucency measured?
Can I avoid this test if I’m healthy?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy