The bleeding that occurs while you take the inactive pills isn't the same as a regular period. Nor is the bleeding necessary for health. This is good news if you take birth control pills and want more control over your menstrual cycle, either for personal or medical reasons.
To prepare for the glucose tolerance diagnostic test: 1  Eat a balanced diet that contains at least 150 grams (g) of carbohydrate per day for 3 days before the test. Fruits, breads, cereals, grains, rice, crackers, and starchy vegetables such as potatoes, beans, and corn are good sources of carbohydrate.
In general, it is recommended that you fast (nothing to eat or drink except water) for at least 8 hours before having a blood glucose test. For people with diabetes, glucose levels are often checked both while fasting and after meals to provide the best control of diabetes. For random, timed, and post-meal glucose tests, follow your health practitioner's instructions.