Hemoglobin A1c Blood Test

Also called: Glycosylated Hemoglobin Test, Glycated Hemoglobin Test

What Is a Hemoglobin A1c Test?

A hemoglobin (HEE-muh-glow-bin) A1c test measures how much a person’s glucose levels have been in and out of the healthy (or target) range during the last 2–3 months.

Hemoglobin is the protein inside red blood cells that carries oxygen. Glucose is a kind of sugar that the body uses for energy. If too much glucose builds up in blood, it binds to hemoglobin and stays attached to it for the life of the red blood cell, or about 2–3 months. A hemoglobin A1c test checks for the amount of this hemoglobin that has glucose attached to it.

Why Are Hemoglobin A1c Tests Done?

Doctors use hemoglobin A1c tests to check for diabetes and to follow how kids with diabetes are doing. The test helps doctors see how well diabetes medicines are working.

Top Things to Know

• A hemoglobin A1c test checks glucose levels in the blood over the last 2–3 months.
• The test results can show if blood sugar has been in a healthy range or not.
• Kids might need to stop taking certain medicines before the blood test.
• Your doctor can explain what it means if hemoglobin A1c levels are high or low.

How Can I Help My Child Prepare for a Blood Test?

Tell your doctor if your child is:

• taking any medicine
• has had a recent blood transfusion
• has a condition (like a blood disorder, liver disease, or kidney disease)

These may change the hemoglobin A1c test results.

To help kids get ready for a blood test, find out if they need to fast (not eat or drink) or should stop taking medicines before the test. Explain what to expect during the test. If your child is nervous about it, work together on ways to stay calm. Deep breathing or even imagining being in a place that makes your child feel safe and relaxed can help.

What Do Hemoglobin A1c Results Mean?

Your doctor will explain what the results of the hemoglobin A1c test mean for your child. What’s “normal” can vary based on things like age and gender.

To diagnose diabetes, doctors usually use these A1c levels:

• less than 5.7%: it’s likely not diabetes
• 5.7%–6.4%: it could be prediabetes (the level is high but it’s not yet considered to be diabetes)
• 6.5% or higher: it might be diabetes

If someone has diabetes, the typical goal is less than 7%.

High Hemoglobin A1c Level

High hemoglobin A1c levels can happen when someone’s blood sugars have been higher than their healthy range. If your child has diabetes, a high level may mean that diabetes medicines need to be adjusted. If your child hasn’t been diagnosed with diabetes but has a high A1c level, it could be prediabetes or diabetes.

Low Hemoglobin A1c Level

An A1c level below 5.7% for kids without diabetes and below 7% for kids with diabetes is usually healthy. Levels that are very low can happen with some blood disorders and diets that are too restrictive.

What Else Should I Know?

Kids with diabetes often need hemoglobin A1c tests every few months to see how treatment is working. If you have questions about the hemoglobin A1c test or what the results mean, talk to your doctor.