The diagnosis of gestational diabetes is made by measuring the amount of glucose in the blood between weeks 24 and 28 of gestation, even when the woman does not show signs and symptoms indicative of diabetes, such as exaggerated increase in appetite or frequent urge to urinate, for example.
Although the exam is usually done after the 24th week, it is also possible that the diagnosis of these weeks is made, especially if you have risk factors related to the occurrence of the disease, such as being overweight, over 25 years of age, family history of diabetes or having had gestational diabetes in a previous pregnancy.
The test to diagnose gestational diabetes mellitus is known as TOTG (Oral Glucose Tolerance Test), in which it is possible to check how the woman's body reacts to large amounts of sugar, since to do this test it is necessary to ingest up to 75 g of a very sugary liquid that is given at the place where the test is done.
How the exam is done
The test for gestational diabetes mellitus, called TOTG, is done between weeks 24 and 28 of gestation following the following steps:
- The pregnant woman must fast for about 8 hours; the first blood collection is made with the fasting pregnant woman; the woman is given 75 g of Dextrosol, which is a sugary drink, in the laboratory or clinical analysis clinic; then, a blood sample is taken immediately after ingesting the liquid; the pregnant woman should be at rest for about 2 hours; then a new blood collection is made after 1 hour and after 2 hours of waiting.
After the examination, the woman can return to normal eating and wait for the result. If the result is altered and there is a suspicion of diabetes, the obstetrician may refer the pregnant woman to a nutritionist to start an adequate diet, in addition to carrying out regular monitoring so that complications for the mother and baby are avoided.
Glucose test results in pregnancy
From the blood collections performed, measurements are made to check blood sugar levels, with normal values considered by the Brazilian Diabetes Society:
| Time after exam | Optimal reference value |
| In fasting | Up to 92 mg / dL |
| 1 hour after exam | Up to 180 mg / dL |
| 2 hours after the exam | Up to 153 mg / dL |
From the results obtained, the doctor makes the diagnosis of gestational diabetes when at least one of the values is above the ideal value.
In addition to the TOTG test, which is indicated for all pregnant women, even those who do not have symptoms or risk factors for gestational diabetes, it is possible that the diagnosis is made before week 24 through the fasting blood glucose test. In these cases, gestational diabetes mellitus is considered when fasting blood glucose is above 126 mg / dL, when blood glucose at any time of the day is greater than 200 mg / dL or when glycated hemoglobin is greater than or equal to 6, 5%. If any of these changes are verified, TOTG is indicated to confirm the diagnosis.
It is important that blood glucose is monitored during pregnancy so that complications for the mother and baby are avoided, in addition to being essential for establishing the best treatment and adequacy of food, which should be done with the help of a nutritionist. Check out some tips in the following video on food for gestational diabetes:
