What is the full form of GTT

GTT: Glucose Tolerance Test

GTT stands for Glucose Tolerance Test. This test is performed to measure the ability of your body cells to absorb glucose or sugar. It is generally used to diagnose type 1 or 2 diabetes, insulin resistance and gestational diabetes. Gestational diabetes usually occurs in women during pregnancy due to the high blood sugar levels due to pregnancy.

There are many variations of the GTT as it is used for different purposes like to diagnose Type 1 or 2 diabetes, gestational diabetes etc. Some of its variations are as follows:

To diagnose diabetes type 1 or 2, a two-hour 75-gram oral glucose tolerance test (OGTT) is used. In this test, you give your blood sample then you drink 8 ounces of a syrup (glucose solution) containing 75 grams of sugar. After drinking it, you have to wait for around two hours before providing another blood sample.
To diagnose the gestational diabetes, your doctor may perform two tests. The first test is same as OGTT except that blood will be drawn at one hour mark and then at two-hour mark as in OGTT. In the second test, there will be one-hour screening where you will consume a syrup containing 50 grams of sugar and then after one hour you will give a blood sample. The one-hour screening will be followed by a three-hour glucose tolerance test if sugar levels are high in the one-hour screening results. The three-hour screening is a three-hour version of the OGTT where you will consume a syrup containing 100 grams of sugar and then you will give a blood sample at one, two and three-hour marks.