Hemoglobin F (Fetal Hemoglobin) Percentage
This test measures the percentage of fetal hemoglobin in your blood. Fetal hemoglobin is the type of hemoglobin found in babies before birth and in some adults with certain blood disorders.
["Fetal hemoglobin percentage helps diagnose conditions like thalassemia or sickle cell disease."]
Key facts at a glance
- LOINC
- 110938-8
- Short code
- Hgb F Msmt Bld
- Synonyms
- Hgb F Msmt Bld
- Category
- hematology
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Ref low
- 12
- Ref high
- 17.5
- Critical range
- 7 N/A – 20 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85018
- SNOMED
- 900000000000003004
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why This Test Is Done
Your healthcare provider may order this test if you have symptoms of blood disorders, such as fatigue, pale skin, or unusual tiredness. It may also be done during pregnancy to monitor fetal health or in adults with genetic blood conditions.
What to Expect Before the Test
No special preparation is needed. You may have a small needle inserted into your arm to draw a blood sample. The process is quick and usually painless.
What the Results Mean
Higher-than-normal levels of fetal hemoglobin can indicate certain blood disorders. Lower-than-normal levels may not be directly related to this test but could be part of broader evaluation for anemia or other conditions.
Common Conditions Linked to Abnormal Results
Elevated fetal hemoglobin is often seen in conditions like beta-thalassemia or sickle cell trait. It may also be present in certain genetic disorders or during pregnancy.
Reference range
Adult males: 13.5-17.5 g/dL; Females: 12.0-16.0 g/dLN/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.
Abnormal results may prompt further testing or evaluation by a specialist, such as a hematologist, to determine the underlying cause and appropriate treatment options.
Short name
HbF %
Frequently asked questions
What causes fetal hemoglobin to be higher than usual?
How is fetal hemoglobin tested?
Can lifestyle changes affect fetal hemoglobin levels?
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