The gestational glucose screening test, typically performed between 24 and 28 weeks of pregnancy, identifies gestational diabetes. Proper preparation is important for accurate results.
Dietary Recommendations Before Your Test
For the one-hour glucose screening test, fasting is generally not required. Eat a balanced breakfast with complex carbohydrates and protein before your appointment. Options include whole-grain toast with avocado or natural peanut butter, plain Greek yogurt with berries, or oatmeal with nuts and sliced apple. Scrambled eggs or an omelet with non-starchy vegetables like broccoli or tomatoes also provide balance. These foods contain fiber and complex carbohydrates, digested slowly to maintain stable blood sugar without rapid spikes.
For a three-hour glucose tolerance test, typically a follow-up to an initial screening, maintain a normal, balanced diet in the days leading up to it. Some healthcare providers recommend consuming at least 150 grams of carbohydrates daily for three days prior. This consistent carbohydrate intake ensures your body’s typical glucose processing is reflected in the test results. Fruits, breads, cereals, rice, and starchy vegetables are good sources to meet these requirements.
Foods to Limit or Avoid
Before your glucose test, limit or avoid certain foods and beverages. Sugary items like soda, fruit juices, sweetened coffee or tea, candy, chocolate, and pastries cause rapid increases in blood sugar. Refined carbohydrates such as white bread, white rice, and processed snacks should also be avoided. These foods quickly break down into sugar, leading to a spike in blood glucose levels.
Consuming these high-sugar or refined carbohydrate foods close to your test can lead to inaccurate results, potentially causing a false positive and necessitating a three-hour glucose tolerance test. While some sources suggest limiting fatty or fried foods due to their potential to slow digestion, the primary focus remains on items that directly impact blood sugar levels.
Fasting and Hydration Instructions
Fasting and hydration instructions vary by glucose test type. For the one-hour glucose screening, fasting is typically not required; you can eat a normal meal beforehand. However, avoid excessive sugar intake in that meal.
The three-hour glucose tolerance test usually requires fasting, meaning no food or drink, other than plain water, for 8 to 14 hours before your initial blood draw. Avoid all other beverages, including coffee, tea, diet sodas, and sugary drinks, during this fasting window. Stay hydrated with plain water before and during the test. Other liquids, chewing gum, and smoking interfere with results and should be avoided. Always follow your healthcare provider’s precise instructions, as protocols differ.