Skip to content

Hemoglobin A1c (HbA1c) with Glycated Hemoglobin Quantification

Published: August 9, 2026Updated: August 16, 2026

This test measures the percentage of hemoglobin in your blood that has been linked to glucose, reflecting your average blood sugar levels over the past 2–3 months.

Quick summary

["HbA1c helps doctors track diabetes management and long-term blood sugar control."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
101470-3
Short code
HBA1+2 THAI Del Bld Ql
Synonyms
HBA1+2 THAI Del Bld Ql
Category
chemistry
Sample
whole-blood
Container
Lavender-top (EDTA)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
molgen
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 HbA1c Measures

HbA1c reflects the amount of glucose (sugar) that has attached to hemoglobin, a protein in red blood cells. It’s a stable marker that integrates blood sugar levels over time, making it useful for assessing chronic diabetes control.

How It’s Used in Care

Doctors use HbA1c to diagnose diabetes, monitor treatment effectiveness, and adjust medications. It’s a key tool for preventing complications like nerve damage, kidney disease, or heart disease.

Sample and Testing Process

A simple blood draw from your arm provides whole blood for this test. The sample is analyzed to determine the proportion of hemoglobin molecules bound to glucose, typically measured via immunoassay or high-performance liquid chromatography (HPLC).

What to Expect Before or After Testing

No special preparation is needed, but fasting isn’t required. Results may take 1–3 business days to return. If you’re pregnant or have certain conditions, your doctor may recommend retesting.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance

Short name

HbA1c

Frequently asked questions

Why is my HbA1c level important?
An HbA1c level helps your doctor determine if your blood sugar is well-controlled. Levels above 6.5% may indicate diabetes, while levels below 5.7% suggest good glycemic control. It’s a long-term indicator that can help prevent serious health issues.
What does an abnormal HbA1c result mean?
A higher-than-normal HbA1c (e.g., 7% or higher) may mean your blood sugar is consistently too high, requiring lifestyle changes or medication adjustments. A lower-than-normal level (e.g., below 5.7%) might indicate you’re managing blood sugar well, but it doesn’t rule out other conditions.
Can HbA1c be affected by other factors?
Yes, factors like recent blood loss, severe illness, or certain medications (e.g., some blood thinners) can temporarily alter HbA1c levels. Your doctor will consider these if results seem unusual.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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