Hemoglobin Mass Fraction in Whole Blood
This test measures the proportion of hemoglobin (the oxygen-carrying protein in red blood cells) relative to the total mass of blood drawn from you. It provides insight into overall red blood cell health and oxygen transport capacity.
Assesses red blood cell function and oxygen delivery in your blood.
Key facts at a glance
- LOINC
- 80656-2
- Short code
- Hgb Hope MFr Bld
- Synonyms
- Hgb Hope MFr 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
What Is This Test Measuring?
Hemoglobin mass fraction is calculated by determining the total amount of hemoglobin in your blood sample and expressing it as a fraction of the blood’s overall weight. Unlike traditional hemoglobin tests (which measure concentration), this method focuses on the absolute mass of hemoglobin, which can be useful in certain clinical scenarios, such as evaluating blood loss or red blood cell production disorders.
Why Might You Need This Test?
This test may be ordered if your healthcare provider suspects conditions affecting red blood cell production, such as anemia due to chronic disease, iron deficiency, or blood loss. It can also help monitor treatments for conditions like polycythemia vera or evaluate responses to blood transfusions.
Common Conditions Monitored
Conditions that may require this test include anemia (low red blood cell production or loss), polycythemia (excess red blood cells), or blood loss from conditions like heavy menstrual bleeding or gastrointestinal bleeding. It can also be part of a broader evaluation for unexplained fatigue or weakness.
How Is This Test Performed?
A small sample of your blood is drawn from a vein, typically in your arm. The sample is processed to separate hemoglobin from other blood components, and the mass of hemoglobin is measured. Results are reported as a fraction (e.g., 0.30 for 30% hemoglobin mass relative to blood weight).
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.
Hemoglobin mass fraction can help identify or monitor conditions where red blood cell production, destruction, or loss is abnormal. For example, low values may indicate anemia, while high values could suggest polycythemia or dehydration. This test complements traditional hemoglobin tests by providing a different perspective on blood composition, particularly in complex cases.
Short name
Hemoglobin Mass Fraction
Frequently asked questions
How long does it take to get results?
What does a low or high result mean?
Can I eat or drink anything before this test?
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