Gestational diabetes Mellitus 75g or 100g of glucose

I was wondering that now a days it's been said that for pregnant women a 100g Glucose and 3 hrs test gives a valid result as compared to 75 g glucose 2hrs test. What do you say about it? I live in Oman and had my GTT with fasting level of 3.89 and after 75 g 2 hrs test 8.6 mm/mol. After this I was required to do a hyperglycemic profile and it was normal. I took the GTT in the evening and I was wondering my high blood sugar level might be due to slow metabolism in the evening. I am now required to repeat the test and I was wondering that should I ask for a 100g Glucose 3 hours test instead of usual 75 g 2 hrs test? Your comments would be really helpful.

Kind Regards
Ritu Mehraa

[WaveRider]

Here are glucose testing values

Fasting Blood Glucose:
From 70 to 99 mg/dL (3.9 to 5.5 mmol/L) - Normal fasting glucose
From 100 to 125 mg/dL (5.6 to 6.9 mmol/L) - Impaired fasting glucose (pre-diabetes)
126 mg/dL (7.0 mmol/L) and above on more than one testing occasion = Diabetes

Oral Glucose Tolerance Test (OGTT):
[except pregnancy]
(2 hours after a 75-gram glucose drink)
Less than 140 mg/dL (7.8 mmol/L) - Normal glucose tolerance
From 140 to 200 mg/dL (7.8 to 11.1 mmol/L) - Impaired glucose tolerance (pre-diabetes)
Over 200 mg/dL (11.1 mmol/L) on more than one testing occasion Diabetes

Gestational Diabetes Screening: Glucose Challenge Test:
(1 hour after a 50-gram glucose drink)
Less than 140* mg/dL (7.8 mmol/L) Normal screen
140* mg/dL (7.8 mmol/L) and over Abnormal, needs OGTT (see below)
* Some use a cutoff of >130 mg/dL (7.2 mmol/L) because that identifies 90% of women with gestational diabetes, compared to 80% identified using the threshold of >140 mg/dL (7.8 mmol/L).


Gestational Diabetes Diagnostic: OGTT
(100-gram glucose drink)
Fasting* 95 mg/dL (5.3 mmol/L)
1 hour after glucose load* 180 mg/dL (10.0 mmol/L)
2 hours after glucose load* 155 mg/dL (8.6 mmol/L)
3 hours after glucose load* ** 140 mg/dL (7.8 mmol/L)
* If two or more values are above the criteria, gestational diabetes is diagnosed.
** A 75-gram glucose load may be used, although this method is not as well validated as the 100-gram OGTT; the 3-hour sample is not drawn if 75 grams is used.