Glycohemoglobin (HbA1c, A1c)
How It Feels
The blood sample is taken from a vein in
your arm. An elastic band is wrapped around your upper arm. It may feel tight.
You may feel nothing at all from the needle, or you may feel a quick sting or
There is very little chance of a
problem from having blood sample taken from a vein.
- You may get a small bruise at the site. You can lower the
chance of bruising by keeping pressure on the site for several minutes.
- In rare cases, the vein may become swollen after the blood
sample is taken. This problem is called phlebitis. A warm compress can be used
several times a day to treat this.
- Ongoing bleeding can be a problem for people with bleeding
disorders. Aspirin, warfarin (Coumadin), and other blood-thinning medicines can
make bleeding more likely. If you have bleeding or clotting problems, or if you
take blood-thinning medicine, tell your doctor before your blood sample is
A1c is a blood test that
checks the amount of sugar (glucose) bound to
hemoglobin . The result is shown as a percentage. The
result of your A1c test can also be used to estimate your average blood sugar
level. This is called your estimated average glucose, or eAG. Your doctor will have your test results in a few days.
The American Diabetes Association (ADA) criteria to diagnose diabetes includes the option of testing A1c. The diagnosis of diabetes needs to be confirmed by repeating the same blood sugar test or doing a different test on another day.
The normal values listed here—called a reference range—are just a guide. These ranges vary from lab to lab, and your lab may have a different range for what's normal. Your lab report should contain the range your lab uses. Also, your doctor will evaluate your results based on your health and other factors. This means that a value that falls outside the normal values listed here may still be normal for you or your lab.
Less than 5.7%
|Prediabetes (increased risk for diabetes)|
6.5% and higher
The ADA recommends that most nonpregnant adults who have diabetes have an A1c level less than 7%.2 Talk to your doctor about your diabetes treatment plan and your target A1c goal.
A1c and estimated average glucose (eAG)2
| A1c %||Estimated average
plasma glucose (mg/dL)||Estimated average plasma glucose (mmol/L)|
A1c recommendations for children and teens2
|Children younger than 6
years old||Less than 8.5%|
|Children ages 6–12 years
old||Less than 8%|
|Teens ages 13–19 years
old||Less than 7.5%|
Some medical conditions can increase A1c levels, but the
results may still be within a normal range. These conditions include
polycystic ovary syndrome (PCOS).
Corticosteroid treatment increases the A1c
A1c levels may be higher in children and adolescents with