Does a glucose tolerance test treat gestational diabetes?

During the test, you drink a measured glucose solution and have blood samples taken according to the instructions from your maternity team. The readings show how your body responds to glucose. Results outside the expected range can support a diagnosis of gestational diabetes, which develops during pregnancy and may affect care even when you feel well.

The test itself does not lower blood glucose or change the underlying condition. A result that suggests gestational diabetes is a reason to discuss a management plan, not a reason to assume that pregnancy complications will occur.

Your clinician may explain home glucose checks, meal planning, suitable physical activity, and follow-up appointments. Some people need medication when glucose readings remain above their agreed targets despite these measures. The plan can be adjusted as pregnancy progresses, so keep a record of readings and any symptoms or difficulties with meals, testing, or medication.

Follow the preparation instructions before the test, including whether you need to fast. Do not change prescribed medicines or deliberately alter your usual intake without checking with the team arranging the test.

Contact your maternity or diabetes team promptly if home readings are repeatedly above the targets they gave you, you cannot keep fluids down, or you are unable to take prescribed treatment. Seek urgent maternity advice for reduced fetal movement, vaginal bleeding, severe abdominal pain, or a severe headache with vision changes. Follow your local emergency guidance for severe illness, confusion, or trouble breathing.

Ask when and how to check your glucose, which targets apply to you, what to do after a high or low reading, and when your results will be reviewed. You can also ask whether a dietitian or diabetes educator can help you plan meals and use the testing equipment.