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Glucose test in pregnancy
glucose tolerance test · GTT · OGTT in pregnancy · gestational diabetes test · glucose drink test
You give blood on an empty stomach, drink a sweet glucose solution, and give blood again after one hour and after two. This checks how your body handles sugar.
Usually at 24 to 28 weeks of pregnancy, to catch gestational diabetes in time. Sometimes earlier, if your doctor sees a reason.
⏱ Duration: about 2 to 2.5 hours; results usually come in 1 to 2 days
Be sure to tell your doctor
How to prepare
- Food. Fasting: usually 8 to 14 hours without food. Plain water is fine.
- The day before. Eat as usual. Do not diet in the days before. In the evening, do not overeat sweets.
- Medicines. Do not stop them on your own. Ask your doctor how to take your morning medicines.
- Time. Keep your morning free. You need to sit quietly at the clinic for 2 hours.
What to bring
- Your referral
- Your pregnancy record
- Water and a snack for after the test
- A book or something to pass the time
How it goes
- In the morning, on an empty stomach, blood is taken from a vein
- You drink a glass of sweet solution within 5 minutes
- You sit quietly. No walking, eating, or drinking
- After one hour, blood is taken a second time
- After two hours, a third time
- Then you can eat
What you'll feel
- The solution is very sweet and may make you feel sick
- Sometimes mild weakness or dizziness. Tell the nurse
- Three needle pricks in the vein
Afterwards
- Eat right after the test
- Results usually come in 1 to 2 days. Your doctor will explain them
- If your sugar is high, your doctor will talk about diet and monitoring
Common questions
Why can't I walk around during the test?
Movement burns sugar and skews the result. You need to sit quietly.
What if I throw up the drink?
Tell the nurse. Usually the test is stopped and moved to another day.
Is the glucose harmful to my baby?
No. It is a normal amount of sugar, like in a sweet drink.