All pregnant women are required to take a glucose tolerance test, to check for the possibility of gestational diabetes, which is a type of diabetes that could develop in some women, during the later stages of their pregnancy, i.e. after they complete 24 weeks. However, in case of a bad history, or concerns about gestational diabetes, this test can be conducted as early as in the thirteenth week of pregnancy. A woman need not have diabetes before becoming pregnant, in order to develop gestational diabetes. This test is a fairly non-invasive test, where blood is drawn from the veins or fingers. There are different ways in which this test can be conducted.
A 1 hour glucose test does not require any fasting. The patient is given 50 grams of a solution that is high in glucose. The entire beverage should be consumed within 5 minutes. As the solution is very sweet, some women may feel nauseous after drinking it. An hour after the beverage is consumed a sample of blood will be drawn. The doctor should be made aware, in case the patient experiences any symptoms of hypoglycemia, like weakness, perspiration or dizziness. If the result of the test indicates that the level of glucose in the blood exceeds 130 mg/dl then another glucose test may be required. However, this time the patient will need to go in for a 3-hour glucose tolerance test.
A 3 hour glucose test is not too different from the one hour test, although there are few distinctions. The patient may be advised to go on a high-carbohydrate diet, for about three days, before taking the test. The patient will be required to fast for about 10 – 14 hours, before taking the test. Pregnant women should try to eat dinner by around 7:00 pm and then fast till morning, till the test is completed. Prolonged fasting should be avoided in pregnancy. Upon arrival at the clinic, the patient’s urine sample will be collected. The patient will then be given 100 grams of a solution, high in glucose. After consumption of the beverage, 4 urine samples will be collected at 30 minutes, at an hour, 2 hours and then 3 hours. Till all five urine samples are collected, the patient will be able to eat or drink anything, except water. A reading of more than 140 mg/ dl indicates gestational diabetes. Once the diagnosis is confirmed, the patient must consult with her doctor at once.