Description
Why It’s Done
The GCT (75g) is performed to:
• Screen for Gestational Diabetes during pregnancy (usually between 24–28 weeks)
• Diagnose Diabetes or Prediabetes in non-pregnant individuals
• Monitor Glucose Tolerance in people at risk of developing diabetes
• Assess Insulin Response to glucose intake
Doctors may recommend this test if you have:
• A family history of diabetes
• Obesity or high BMI
• History of gestational diabetes or large babies
• Polycystic ovary syndrome (PCOS)
Preparation
To prepare for a 75g GCT:
• Fasting is required: Do not eat or drink anything (except water) for at least 8–10 hours before the test.
• Avoid smoking and caffeine before and during the test.
• Inform your doctor about any medications you are taking, as some can affect your blood sugar levels.
• Duration: You will be required to stay at the lab or clinic for approximately 2 to 3 hours.
• Procedure:
1. A fasting blood sample is taken first.
2. You will drink a solution containing 75 grams of glucose.
3. Additional blood samples are collected at 1 hour and 2 hours after drinking the solution.
