Glucose Screen and Tolerance Tests
Author: Carla Snuggs
At around 24 to 28 weeks of pregnancy, most practitioners will perform a routine check for gestational diabetes using a glucose screening test. Gestational diabetes is a condition that happens only during pregnancy and usually goes away postpartum. When you aren’t producing enough insulin (which regulates blood sugar), it can lead to problems for you and your unborn baby including preeclampsia and jaundice. In addition, your baby could be born large for gestational age.
Glucose Screening Test
For the test, you will be asked to drink a sweet liquid containing glucose, and then have your blood drawn an hour later. This test will check your glucose levels. If the results of your glucose screening test reveal elevated numbers, this could mean that you may not be producing enough insulin. Your doctor will then order an oral glucose tolerance test.
Preparing for the Oral Glucose Tolerance Diagnostic Test
In order to prepare for the oral glucose tolerance diagnostic test, the National Institutes of Health suggests that you:
- Eat normally for 3 days before the test; then, do not eat or drink anything after midnight before the test.
- Make sure to tell your health professional about all prescription and nonprescription medicines you are taking. In some cases, your practitioner may instruct you to stop taking certain medicines before the test.
Oral Glucose Tolerance Test
- Your blood will be drawn in order to provide your fasting blood glucose value.
- You will be asked to drink a liquid containing glucose.
- Blood samples will be collected at one hour, two hours, and 3 hours after you drink the glucose. Sometimes, blood samples are taken after 30 minutes and more than 3 hours after you drink the glucose.
Four to seven percent of pregnant women are diagnosed with gestational diabetes, so it is important to take the glucose screening test ordered by your physician. If you are then diagnosed with gestational diabetes, it can easily be monitored and managed with diet, exercise, and/or medication.
