Hemoglobin A1c (HbA1c) measured by high-performance liquid chromatography (HPLC)
This test measures the average blood sugar level over the past 2–3 months by examining the percentage of hemoglobin molecules that have sugar attached. It helps doctors assess long-term blood glucose control.
["HbA1c reflects your blood sugar trends over time, aiding diabetes management."]
Key facts at a glance
- LOINC
- 49137-3
- Short code
- Hgb Ur Strip-mCnc
- Synonyms
- Hgb Ur Strip-mCnc
- Category
- hematology
- Sample
- urine
- Container
- Sterile urine container
- 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
- Method
- test-strip
- CPT
- 85018
- SNOMED
- 900000000000003004
- Specimen volume
- 10 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why Is This Test Done?
Doctors order HbA1c tests primarily to diagnose type 1 or type 2 diabetes and monitor blood sugar levels in people with diabetes. It’s also used to check if current treatments are working effectively.
How Is the Test Performed?
A small blood sample is taken from your arm, usually by a healthcare professional. The blood is sent to a lab where it’s analyzed using high-performance liquid chromatography (HPLC) to measure the percentage of hemoglobin with attached sugar.
What Do the Results Mean?
Results are reported as a percentage (e.g., 5.7% or 7.2%). While specific ranges vary by lab, higher percentages generally indicate poorer blood sugar control. Your doctor will interpret results in the context of your overall health.
What Are Common Causes of Abnormal Results?
Elevated HbA1c levels may suggest uncontrolled diabetes, while lower levels could indicate well-managed blood sugar or conditions like anemia. Other factors, such as pregnancy or certain medications, can also affect results.
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.
◆Associated findings1
Short name
HbA1c (Blood Sugar Average)
Frequently asked questions
How often should I get an HbA1c test if I have diabetes?
Can lifestyle changes, like diet or exercise, affect my HbA1c results?
What if my HbA1c is higher than expected, but I don’t have diabetes symptoms?
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