Hemoglobin A1c (HbA1c) by Electrophoresis
This test measures the average level of blood sugar (glucose) over the past 2–3 months by analyzing hemoglobin in your red blood cells.
["Helps track long-term blood sugar control for diabetes management."]
Key facts at a glance
- LOINC
- 4558-3
- Short code
- Hgb Barts Bld Ql Elph Acid
- Synonyms
- Hgb Barts Bld Ql Elph Acid
- 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
- Method
- electrophoresis-ph
- 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 Does This Test Measure?
HbA1c reflects your blood sugar levels over time because hemoglobin stays in red blood cells for about 120 days. It’s a key indicator of how well your diabetes is managed, especially if you’ve had it for several years.
Why Is This Test Important?
Regular HbA1c testing helps prevent complications like nerve damage, kidney disease, or heart disease by showing whether your blood sugar stays within healthy ranges.
How Is This Test Done?
A small blood sample is taken from your arm, usually during a routine visit. The sample is then analyzed using electrophoresis to separate hemoglobin types and measure HbA1c levels.
What Are Common Results?
Results are reported as a percentage (e.g., 6.5%). While exact ranges vary by lab, higher percentages indicate poorer blood sugar control, while lower ones suggest better management.
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.
Clinical Significance: HbA1c is a gold-standard marker for diabetes management. Values above 7% may signal uncontrolled diabetes, prompting adjustments to treatment (e.g., diet, medication). It’s also used to assess prediabetes (5.7–6.4%) or preexisting diabetes progression.
Short name
HbA1c
Frequently asked questions
How often should I get this test?
What does an abnormal HbA1c result mean?
Can diet or exercise affect HbA1c results?
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