How long does it take to see a change in the A1C test or eAG?

With the A1C test or eAG, it takes about 2 to 3 months to see all the results of an improvement (or worsening) in blood glucose. This is why there’s really no need to have the test more often than every 3 months. However, if you are newly diagnosed and may have been far out of range for a while, you may want to have your A1C measured every 2 weeks at first. Significant changes in blood glucose can be seen within 2 weeks. Or, for someone who is pregnant and seeking very tight glucose levels, A1C may be measured every month or two to make sure that the treatment plan is getting results.

Continue Learning about Diabetes


Diabetes mellitus (MEL-ih-tus), often referred to as diabetes, is characterized by high blood glucose (sugar) levels that result from the body’s inability to produce enough insulin and/or effectively utilize the insulin. Diabetes ...

is a serious, life-long condition and the sixth leading cause of death in the United States. Diabetes is a disorder of metabolism (the body's way of digesting food and converting it into energy). There are three forms of diabetes. Type 1 diabetes is an autoimmune disease that accounts for five- to 10-percent of all diagnosed cases of diabetes. Type 2 diabetes may account for 90- to 95-percent of all diagnosed cases. The third type of diabetes occurs in pregnancy and is referred to as gestational diabetes. Left untreated, gestational diabetes can cause health issues for pregnant women and their babies. People with diabetes can take preventive steps to control this disease and decrease the risk of further complications.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.