Glucose tolerance test:Normal range Pregnancy

 Glucose tolerance test

glucose tolerance test solution

What is a glucose tolerance test and how does it work?

glucose tolerance test normal range - 80-100 mg/dl (serum glucose)

glucose tolerance test definition - Oral glucose tolerance test is performed for patiens with borderline fasting plasma glucose value(i.e. between 100-140mg/dl).The patient who is scheduled for oral glucose tolerance test is instructed to eat a high carbohydrate diet for at least 3 days prior to the test and come after overnight fasting on the day of the test (for at least 8 hours)(glucose tolerance test fasting).

 A fasting blood sugar sample is drawn.Then 75 gm of glucose dissolved in 300 ml water is given. Blood and urine specimen are collected at half hourly intervals for at least 2 hours. Blood or plasma glucose content is measured and urine is tested for glycosuria to determine the approximate renal threshold for glucose. Venous whole blood concentration are 15% lower than plasma values.

Currently accepted criteria for diagnosis of diabetes mellitus(as per American Diabetes Association,2007)

Normal cuttoff value for fasting blood glucose level is considered as 100mg/dl.

Cases with fasting blood glucose value in range of 100-125mg/dl are considered as impaired fasting glucose tolerance(IGT): these cases are at increased risk of developing diabetes later and therefore kept under observation for repeating the test. During pregnancy,however, a case of IGT is treated as a diabetic.

Individual with fasting value of plasma glucose higher than 126mg/dl and 2 hours value after 75 gm oral glucose higher than 200mg/dl are labelled as diabetics.

In symptomatic case,the random blood glucose value above 200mg/dl is diagnosed as diabetes mellitus.

How is a glucose tolerance test performed?

Steps of glucose tolerance test procedure -

1. Patient is instructed to eat high carbohydrate diet 3 days prior to glucose tolerance test.

2.After an overnight fasting on the day of test(for atleast 8 hours),a blood sample is drawn.

3.Then 75 gm of glucose dissolved in 300 ml of water is given to patient.

4.Blood and urine sample are collected at half hourly intervals for atleast 2 hours.

5.Blood or plasma glucose content is measured and urine is tested for glycosuria to determine the approximate renal threshold for glucose.

What is a normal GTT test result?

Normal glucose tolerance test value = 100-125 mg/dl

What is meant by glucose tolerance?

Glucose tolerance test check the ability of a person to hold or tolerate glucose load.

oral glucose tolerance test pregnancy

(2 hour glucose tolerance test pregnancy normal range)

Cases with fasting blood glucose value in range of 100-125mg/dl are considered as impaired fasting glucose tolerance(IGT): these cases are at increased risk of developing diabetes later and therefore kept under observation for repeating the test. During pregnancy,however, a case of IGT is treated as a diabetic.

Glucose tolerance test results -

Normal blood glucose level  80-100 mg/dl

Impaired fasting glucose tolerance (IGT) 100-125 mg/dl

During pregnancy ,however a case of IGT is treated as a diabetic patient.

Diabetic patient - glucose level higher than 126 mg/dl and 2 hour value after 75 gm oral glucose higher than 200 mg/dl are labelled as diabetic.