The 2-hour, 3-sample GTT is typically performed between 24 and 28 weeks of pregnancy, when gestational diabetes is most likely to develop. During the test, you will be asked to fast overnight and avoid food or drink (except water) for at least 8-12 hours before the test. This ensures that your blood sugar levels are at their baseline, providing the most accurate results.Initial Blood Draw: The test begins with a fasting blood sample to measure your glucose level before you consume any sugary liquid.

Glucose Drink: After the first blood sample, you’ll drink a glucose solution that contains a specific amount of sugar (usually 75g of glucose for this test). The drink may feel sweet or syrupy, but it’s important to finish it within a few minutes.

Subsequent Blood Draws: After drinking the glucose solution, your blood will be drawn again at 1 hour and 2 hours to check how your body is responding to the sugar intake. These samples help track how efficiently your body is processing glucose over time.

The glucose levels from all three blood samples are analyzed to determine whether your body is having trouble processing glucose, which is a hallmark of gestational diabetes. If your blood glucose levels are higher than the normal range at any of the three intervals, it may indicate gestational diabetes, and your healthcare provider will suggest next steps for management and care.