And for those who still don't have an idea or knowledge what this test is and why it is necessary for a pregnant woman to undergo through, here is an information from Babycenter:
My practitioner says I need a glucose screen. Why?
Most healthcare practitioners routinely recommend a glucose screening test (also called a glucose challenge test or GCT) between 24 and 28 weeks of pregnancy to check for gestational diabetes, a high blood sugar condition that some women get during pregnancy.
Like any screening test, this one won't give you a diagnosis – it's designed to identify as many women as possible who may have a problem and need more testing to find out. So a positive result doesn't mean that you have gestational diabetes. In fact, only about a third of women who test positive on the glucose screen actually have the condition. To find out whether you're one of them, you'll have to undergo a longer, more definitive exam called a glucose tolerance test (GTT).
Between 2 and 5 percent of expectant mothers develop gestational diabetes, making it one of the most common health problems during pregnancy. And because the condition rarely causes any symptoms, testing is the only way to find out whether you have it.
Your practitioner may want you to be screened earlier than 24 weeks if a routine urine test shows a high amount of sugar in your urine or if you're considered at high risk. If the results are normal, you'll be screened again at 24 to 28 weeks.
Of course, if you were already diagnosed with diabetes before pregnancy, you won't need to be screened. Instead, you'll continue to work with your practitioner to manage your condition during pregnancy.
How is the screening test done?
When you arrive for the test, you'll be given a sugar solution that contains 50 grams of glucose. The stuff tastes like a very sweet soda pop (it comes in cola, orange, or lime flavor), and you have to get all of it down in five minutes. Some centers keep it chilled or let you pour it over ice and drink it cold.
An hour later (bring a book or magazine!), your practitioner or a technician will take a blood sample from your arm to check your blood sugar level. The idea is to see how efficiently your body processes sugar. The results should be available in a few days.
If the reading is too high, which happens 15 to 23 percent of the time, your practitioner will have you come back for a three-hour glucose tolerance test to see whether you really do have gestational diabetes. The good news is that most women whose screening test shows elevated blood sugar don't turn out to have gestational diabetes.
Will this test make me feel sick?
Some moms-to-be feel nauseated after drinking the glucose solution, and a few even throw up. It may help to eat something a few hours before the screening test. If you vomit soon after you've gotten the drink down, you'll have to come back another day and repeat the test. But most women get through it just fine.
It's actually more common for women to feel sick during the three-hour glucose tolerance test, because the solution for that test may be twice as sweet or contain twice as much liquid as the one for the screening test, and you have to drink it after fasting.
What is an abnormal blood glucose level?
Different practitioners use different standards for determining whether your level is too high. Some will say that if your one-hour blood sugar level is 140 milligrams of glucose per deciliter of blood plasma (mg/dL) or more, you need to have the glucose tolerance test. Others put the cutoff at 130 mg/dL to catch more women who may have gestational diabetes, even though there are likely to be more false positives this way.
If your blood glucose level for this screening is higher than 200 mg/dL, most practitioners will consider you diabetic and you won't be required to take the glucose tolerance test. But any score between 140 and 200 means that you'll have to take the three-hour glucose tolerance test for a definite diagnosis.
What is the glucose tolerance test like?
For three days before the test, you'll be told to eat at least 150 grams of carbohydrate a day. If you eat a normal diet and have an extra piece of bread at each meal, you'll likely be getting enough carbs. For eight to 14 hours before the test, you can't eat or drink anything but sips of water (and you're not supposed to smoke or exercise either), so you'll want to schedule the test for first thing in the morning.
When you arrive for the test, the technician will take a blood sample to measure your fasting blood glucose level and then ask you to drink either a more concentrated dose or a larger volume of the glucose solution. Then brace yourself for three more arm pricks, as your blood is tested every hour for the next three hours. The technician should alternate arms each time your blood is drawn.
You'll definitely need something to distract you this time, because you'll have to stay seated in the waiting room when you're not getting your blood drawn. And bring something to eat right after your final blood sample is taken because you'll probably be starving.
If one of the readings is abnormal, you may have to take another test later in your pregnancy. Or your practitioner may ask you to make some changes in your diet and exercise routine.
If two or more of your readings are abnormal, you'll be diagnosed with gestational diabetes and you'll need to talk to your practitioner about a treatment plan. This chart shows the levels that the American Diabetes Association considers abnormal at each interval of the test:
Interval Abnormal reading
Fasting 95 mg/dl or higher
1 hour 180 mg/dl or higher
2 hours 155 mg/dl or higher
3 hours 140 mg/dl or higher
Photo courtesy of www.ladycarehealth.com
When you arrive for the test, you'll be given a sugar solution that contains 50 grams of glucose. The stuff tastes like a very sweet soda pop (it comes in cola, orange, or lime flavor), and you have to get all of it down in five minutes. Some centers keep it chilled or let you pour it over ice and drink it cold.
An hour later (bring a book or magazine!), your practitioner or a technician will take a blood sample from your arm to check your blood sugar level. The idea is to see how efficiently your body processes sugar. The results should be available in a few days.
If the reading is too high, which happens 15 to 23 percent of the time, your practitioner will have you come back for a three-hour glucose tolerance test to see whether you really do have gestational diabetes. The good news is that most women whose screening test shows elevated blood sugar don't turn out to have gestational diabetes.
Will this test make me feel sick?
Photo courtesy of www.abeautyfullday.com
Some moms-to-be feel nauseated after drinking the glucose solution, and a few even throw up. It may help to eat something a few hours before the screening test. If you vomit soon after you've gotten the drink down, you'll have to come back another day and repeat the test. But most women get through it just fine.
It's actually more common for women to feel sick during the three-hour glucose tolerance test, because the solution for that test may be twice as sweet or contain twice as much liquid as the one for the screening test, and you have to drink it after fasting.
What is an abnormal blood glucose level?
Different practitioners use different standards for determining whether your level is too high. Some will say that if your one-hour blood sugar level is 140 milligrams of glucose per deciliter of blood plasma (mg/dL) or more, you need to have the glucose tolerance test. Others put the cutoff at 130 mg/dL to catch more women who may have gestational diabetes, even though there are likely to be more false positives this way.
If your blood glucose level for this screening is higher than 200 mg/dL, most practitioners will consider you diabetic and you won't be required to take the glucose tolerance test. But any score between 140 and 200 means that you'll have to take the three-hour glucose tolerance test for a definite diagnosis.
What is the glucose tolerance test like?
For three days before the test, you'll be told to eat at least 150 grams of carbohydrate a day. If you eat a normal diet and have an extra piece of bread at each meal, you'll likely be getting enough carbs. For eight to 14 hours before the test, you can't eat or drink anything but sips of water (and you're not supposed to smoke or exercise either), so you'll want to schedule the test for first thing in the morning.
When you arrive for the test, the technician will take a blood sample to measure your fasting blood glucose level and then ask you to drink either a more concentrated dose or a larger volume of the glucose solution. Then brace yourself for three more arm pricks, as your blood is tested every hour for the next three hours. The technician should alternate arms each time your blood is drawn.
You'll definitely need something to distract you this time, because you'll have to stay seated in the waiting room when you're not getting your blood drawn. And bring something to eat right after your final blood sample is taken because you'll probably be starving.
If one of the readings is abnormal, you may have to take another test later in your pregnancy. Or your practitioner may ask you to make some changes in your diet and exercise routine.
If two or more of your readings are abnormal, you'll be diagnosed with gestational diabetes and you'll need to talk to your practitioner about a treatment plan. This chart shows the levels that the American Diabetes Association considers abnormal at each interval of the test:
Interval Abnormal reading
Fasting 95 mg/dl or higher
1 hour 180 mg/dl or higher
2 hours 155 mg/dl or higher
3 hours 140 mg/dl or higher
What happens if I'm diagnosed with gestational diabetes?
Photo courtesy of www.womenhealthzone.com
You'll work with your practitioner or a diabetes specialist and possibly a nutritionist to come up with a plan to manage your condition. Your high blood sugar should only last as long as your pregnancy – but a small number of women who develop diabetes during pregnancy still have it after delivery, so you'll have to take another glucose test six to eight weeks after your baby is born.
Data Source: Babycenter http://www.babycenter.com/0_glucose-screening-and-glucose-tolerance-tests_1483.bc
