Glucose challenge test

The glucose challenge test measures your body's response to sugar (glucose). The glucose challenge test is done during pregnancy to screen for gestational diabetes — diabetes that develops during pregnancy.

The glucose challenge test is done in two steps. First you drink a sugary solution. One hour later, your blood sugar level is measured. The results of the glucose challenge test indicate whether you might have gestational diabetes.

If the test results are above normal, you'll need to have further testing to determine the diagnosis.


Why it's done How you prepare What you can expect Results

The glucose challenge test is used to screen for gestational diabetes. The test is generally done between weeks 24 and 28 of pregnancy.

However, it can be done as early as your first prenatal visit if you're at high risk of gestational diabetes due to obesity, a personal history of gestational diabetes, a family history of diabetes or other factors. Abnormal test results early in pregnancy might indicate that you have pre-existing type 2 diabetes that wasn't previously recognized — not gestational diabetes.

Most women who have gestational diabetes deliver healthy babies. However, without careful management, gestational diabetes can lead to various pregnancy complications, such as excess fetal growth — which might increase the risk of birth injuries or prompt a C-section delivery.

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