Oral Glucose Tolerance Test (OGTT)

Test Overview

The oral glucose tolerance test (OGTT) measures the body's ability to use a type of sugar, called glucose, that is the body's main source of energy. An OGTT can be used to diagnose prediabetes and diabetes. An OGTT is most commonly done to check for diabetes that occurs with pregnancy (gestational diabetes). The test can be done on its own or as the second test in a two-part screening for pregnant women.