How to Take a Pregnancy Glucose Tolerance Test

Most obstetricians recommend that pregnant women take a glucose screening test between the 24th and 28th week of pregnancy. This test determines how well a woman processes sugar. Poor processing can indicate the presence of gestational diabetes, a serious pregnancy complication. Your doctor may recommend a second glucose tolerance test to confirm the presence of gestational diabetes.

Instructions

Difficulty: Easy

1. Take the glucose-screening test toward the end of your second trimester. This involves drinking a solution of glucose that tastes like very sweet cola. After an hour passes, the doctor draws your blood to see how well you processed the sugar. If your body did not process the sugar well (as in the case of 15 to 23 percent of pregnant women), you may have to come back for a 3-hour glucose tolerance test.
2. Interpret the results of your glucose screening. If your 1-hour blood sugar level is between 140 mg/dL (milligrams per deciliter) and 200 mg/dL of blood plasma, you must take the follow-up glucose tolerance test. If your blood sugar level is higher than 200 mg/dL, this indicates that you have gestational diabetes and do not have to take the second glucose tolerance test.
3. Undergo the 3-hour glucose tolerance test. The 3 days before the test, eat at least 150 g of carbohydrates per day. Schedule your test for the morning, as it is a fasting test. You may not eat, drink, smoke or exercise the morning of the test. You must drink another glucose solution (generally one that is stronger or of a greater volume than the glucose screening test). A lab technician will draw your blood once an hour and note the results.
4. Understand the results of the glucose tolerance test. If two or more of your levels are higher than the recommended maximums, with a diagnosis of gestational diabetes, you must formulate a treatment plan with your doctor. The recommended maximum glucose levels are as follows: fasting—95 mg/dL, 1 hour—180 mg/dL, 2 hours—155 mg/dL and 3 hours—140 mg/dL.
5. Know the risk factors for getting gestational diabetes. It is especially important for the following women to get their glucose levels screened, as they are at a higher risk for developing gestational diabetes. Women who had gestational diabetes during a prior pregnancy, have birthed a baby weighing more than 8.8 pounds, or are younger than 25 and were overweight when they became pregnant are at the highest risk of developing the condition.