Health & Pregnancy

Results continued...

You have prediabetes if the results of your oral glucose tolerance test are 140 to 199 mg/dL (2 hours after the beginning of the test).

High values

High glucose levels may be caused by:

• Diabetes.
• Gestational diabetes.
• Hyperthyroidism.
• Taking medicines, such as corticosteroids, niacin, phenytoin (Dilantin), some diuretics, and some medicines used to treat high blood pressure, HIV, or AIDS.
• Large amounts of the hormone cortisol in the blood (Cushing's syndrome).
• Inherited diseases, such as hemochromatosis.
• Pheochromocytoma.

Low values

Low glucose levels may be caused by:

• Certain medicines, such as medicines used to treat diabetes, some blood pressure medicines (such as propranolol), and some medicines for depression (such as isocarboxazid).
• Decreased production of the hormones cortisol and aldosterone (Addison's disease).
• Problems with the thyroid gland (hypothyroidism) or an underactive pituitary gland.
• A tumor or other problems of the pancreas.
• Liver disease.

Many conditions can change blood glucose levels. Your doctor will discuss any significant abnormal results with you in relation to your symptoms and past health.

What Affects the Test

Reasons you may not be able to have the test or why the results may not be helpful include:

• Smoking.
• Taking certain medicines, such as corticosteroids, diuretics, seizure medicines, birth control pills, nonsteroidal anti-inflammatory drugs (NSAIDs), and some medicines used to treat high blood pressure.
• Alcohol.
• Recent surgery, illnesses, and infectious diseases.
• Weight loss through dieting.
• Long periods of bed rest (such as from a hospitalization or illness).

What To Think About

If you are diagnosed with gestational diabetes, you have a higher risk of developing diabetes later in life. The American Diabetes Association recommends screening for diabetes and prediabetes every three years.²