Glycemic curve in pregnancy: the test that evaluates the risk of gestational diabetes
The glycemic curve in pregnancy (also known by the acronym of GCT, Glucose Challenge Test) is an important test for the diagnosis of gestational diabetes, a rather common disease that affects about 8% of pregnant women in Italy and is more frequent. in those over the age of 35.
The glycemic curve in pregnancy is not an invasive test and must be repeated during gestation only if the values found are not normal. It serves, in fact, to identify the presence of alterations in the metabolism of carbohydrates, and it does so by measuring the concentration of sugars in the blood, before and after having administered glucose orally to the pregnant woman, thus verifying any "glycaemia".
The glycemic curve in pregnancy is very similar to another test called the "oral glucose load test", but unlike the latter, fasting is not required before the test and the oral glucose solution given to the woman is different. Let's find out together everything there is to know on the subject, the causes that can alter the curve, when it is necessary to do the examination and the interpretation of the results. But first, here's a video on foods to watch out for during pregnancy:
What are the causes that can alter the glycemic curve in pregnancy?
The glycemic curve in pregnancy is important to indicate - if the values are altered - the presence of gestational diabetes. Gestational diabetes is a disease that involves poor glucose tolerance: women who suffer from it have difficulty in producing insulin, the hormone that has the function of extracting glucose from the blood and transforming it into energy.
During pregnancy, the hormones that arise from the placenta determine an increased resistance of the tissues to insulin, and if on the one hand this can be considered physiological because it is necessary for the fetus to be fed in the best possible way, on the other the risk factors increase. if the pancreas does not secrete an additional quantity of insulin: the glycaemia, if this does not happen, will remain at high levels, leading to the onset of gestational diabetes.
People with gestational diabetes have high blood sugar because their blood has very high levels of glucose. The women who suffer from it, in the vast majority of cases, recover after childbirth and neither mother nor child are harmed. In other cases, however, gestational diabetes can lead to the development of preeclampsia and the baby may experience breathing difficulties, jaundice, risk of obesity and the development of type 2 diabetes. difficult the moment of delivery.
Symptoms that characterize gestational diabetes are chronic fatigue, frequent urination, increased sense of hunger along with weight loss, presence of infections. In these cases, taking care of your diet is essential to keep the problem at bay, as is physical exercise compatible with your pregnancy.
When is it necessary to take this exam?
This test is prescribed to all pregnant women between the 24th and 28th week of pregnancy who have at least one of the following risk factors: family members with first degree diabetes, fetal macrosomia in previous pregnancies (with a child born with a heavier weight) 4.5 kg), overweight, 35 years of age or older, belonging to an "ethnic group most at risk (Asian, Middle Eastern, Caribbean).
The test will instead be carried out already between the 16th and 18th week of pregnancy in case of obesity, previous gestational diabetes, high blood sugar before or at the beginning of gestation (with fasting values equal to 100-125 mg / dl). diagnosed with gestational diabetes, the examination will be repeated 8-12 weeks after the birth for control.
How is the test performed?
The examination of the glycemic curve in pregnancy is carried out, as anticipated, by administering certain dosages of glucose to the pregnant woman: 50 grams for the screening test for gestational diabetes and 100 grams for the oral glucose load test, which it is used to confirm the diagnosis of diabetes and should be performed in the event that the pregnant woman has glycemic values higher than 140 mg / dl one "hour after" the glycemic curve test is performed.
The test begins with a blood test to detect the basic blood glucose values, and then passes to the administration of 50 grams of glucose. The pregnant woman waits for an hour without eating or smoking (trying to remain seated and as relaxed as possible). After one hour, the second blood sample is taken to check the new results.
If the glycaemia, after an hour, is equal to or greater than 140 mg / dl, but less than 180 mg / dl, the test can be considered positive and the oral glucose load must be examined, with the administration of 100 grams to confirm the diagnosis of gestational diabetes. If, on the other hand, the values are higher than 180 mg / dl, diabetes can be diagnosed directly, without having to resort to the next test.
The latter is carried out by taking a sample for the basal fasting blood glucose, and then having the woman take 100 grams of glucose dissolved in water. hour, 120 and 180 minutes. If two or three values are higher than the reference values, diabetes can be diagnosed. If only one value is higher, however, the diagnosis will be that of glucose intolerance in pregnancy.
Interpretation of the test results
Glycemic values in pregnancy are considered normal if they are up to 95 mg / dl immediately after taking glucose; not higher than 180 mg / dl after one "hour from" intake; below 155 mg / dl after 120 minutes.
The normal values for the oral load test are instead lower than 95 mg / dl fasting; less than 180 mg / dl after one "hour from" intake; less than 155 mg / dl after 2 hours.
If you are diagnosed with gestational diabetes, don't worry: in most cases, as we said, there will be no risk to you and the unborn baby. It will be good, however, to adopt a healthier lifestyle, taking care of your diet and doing physical movement. Regular weight and blood glucose checks will also be needed.
For further scientific information on the subject, you can consult the website of the San Gaetano Polyclinics.
