Tests to determine GDM

All mothers who may be prone to develop Gestational Diabetes would be asked to do some blood tests by their doctors.

Different tests may be used by different doctors depending on the history and condition of the would be mothers and also the prevailing local practices and professional guidelines.

This Test is called Glucose Tolerance test. It may be done in two steps or in one step as your doctor would consider better. Some doctors also use the standard glucose tolerance test which may require only two tests of Blood glucose .

WHO guidelines 

WHO recommends  Testing blood glucose while fasting (after 10 hrs of fast) and 2 hrs after taking 75 gms of glucose.

Normal values are 

Fasting - less than 90 mg/dl

2 hrs post 75 gms of glucose - less than 140

ADA guidelines

The criteria set by the American Diabetes Association to Diagnose GDM are as follows

Step One 

First you have to give a fasting blood glucose sample, after which you would be given a a sweet liquid or juice containing 50 gms of glucose. Blood is again tested for glucose after 1 hour. 

If the Blood glucose after 1 hour is less than 140 mg/dl no further testing would be required.

Step Two 

If the Blood glucose levels were more than 140mg/dl after 1 hour then an Oral Glucose Tolerance (OGTT) test is done.

In this test blood is tested four times.

At the time of fasting

1 hour after taking 100 gms of glucose powder or drink,

at two hrs and three hours.

Normal values should be

Fasting - less than  95

After taking 100 gm glucose - at:

1 hour less than 180

2 hour less than 155

3 hour less than 140

If more than 2 values are abnormal, the mother may be considered to be having Gestational Diabetes.

( Please consult your doctor for specific details)

Latest News 

Latest research done on more than 12000 pregnant mothers have shown that blood glucose levels after 2 hrs of taking 75 gms of glucose should be less than 120 mg/dl

 Glycosylated Hemoglobin ( HbA1C or just A1C)

 This test shows the average blood glucose values prevailing over past three months, sometimes this test may also be ordered by your doctor to asess the glucose levels in past few months. Normal levels should be less than 6.5 % during pregnancy.