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Glucose tolerance test instructions

This is a routine test that is performed between 24 and 28 weeks to screen for Gestational Diabetes. This test does not diagnose Diabetes, rather is an indicator to perform further testing if the initial one hour test is high.

  • You cannot eat or drink 2 hours prior to your appointment time. (This includes water)
  • You may refrigerate your drink, but do not drink over ice. The ice will water down the test, resulting in false results.
  • Drink the Oral Glucose Tolerance Beverage within 5 minutes, 30 minutes prior to your appointment time.
  • Your blood must be drawn at exactly one hour after you have completed the beverage.
  • Notify the front desk upon arrival as to the time you finished your drink.
  • Do not eat or drink until after your blood is drawn.

Remember: You must drink the entire contents within 5 minutes.

You will have a separate appointment for the lab prior to your routine prenatal visit. This is to ensure that your test is drawn at the proper time. Delay in drawing your blood for the Glucose Tolerance Test can negatively affect the results and you will have to repeat the test again.

*Any questions please contact us through MyChart at or 704-316-2021

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