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Date of last update: 10/17/2017.

Forum Name: Diabetes

Question: I failed my one hr glucose test and took the 3 hr today!

 mrsflynn - Fri Aug 06, 2010 12:35 am

I'm just wondering if someone can help me here! My doctor says i have gestational diabetes but when i look at the results they look normal! I failed my first test with a blood sugar level of 138. I took the 3 hr test today but ended up throwing up half way through the test. They told me that it wouldn't matter because as long as i kept the drink down for 30 mins the glucose would be absorbed already! Please help these are my results from today!

Fasting Glucose 100 70-110 mg/dL
Drawn at/Drawn by: 0720
Glucose at 1 Hour 179 70-190 mg/dL
Drawn at/Drawn by: 0852
Glucose at 2 Hour 110 70-165 mg/dL
Drawn at/Drawn by: 0952
Patient threw up at 0913. JD
Glucose at 3 Hour 92 70-145 mg/dL
Drawn at/Drawn by: 1052
 Dr.M.Aroon kamath - Fri Aug 13, 2010 1:08 am

User avatar Hi,
To interpret the OGGT values provided and to offer any recommendations, one needs to know exactly which type of test was carried out(a 50 gm or a 100 gm OGTT) and also, at how many weeks of pregnancy the test was performed.

A 50 gm 1 hour OGGT is useful as a screening test generally performed at 24-28 wks of pregnancy.

The 2 hour and 3 hour OGGTs are generally recommended due to the following reasons.
- in some normal individuals, the rapid emptying of the stomach contents(glucose) into the duodenum tends to cause a sudden large glucose level spike initially, before settling down by about 2 hours due to insulin action.
- in others with slow gastric emptying, the initially the spike is low and the entire OGGT curve may remain rather 'flat'.

These are some of the reasons why a full 2 or 3 hour OGGT is recommended.

There is general consensus regarding the reliability of the 50 gm 1 hour OGGT as a screening test. But,the 2 and 3 hour tests have been subject to considerable disagreement as to their interpretation.

In non-pregnant women, a peak value of >200 mg/dl and a 2 hour value of >200 mg/dl are necessary for diagnosis of diabetes mellitus (DM). The National Diabetes Data Group (NDDG) criteria for gestational DM (for a 100 gm 3 hour OGGT) are,
- a 1 hour value of 190mg/dl (10.5 mmol) or more,
- a 2 hour value of 165 mg/dl (9.2 mmol) or more, and
- a 3 hour value of 145 mg/dl (80 mmol) or more.

To draw 'reliable' conclusions about the diabetic status, atleast 2 OGGT values must be "diabetic".
If only a single value is abnormal in a 100 gm test, the test should be repeated after an interval of a month.

It has also been observed that nearly 25% of the initially "normal" or "impaired" OGGT results may change significantly for the worse with advancing pregnancy.

There is growing evidence and concern that even one abnormal value during pregnancy is sufficient enough to have a significant impact on the health of the growing fetus.

With these facts in mind, i suggest that you should
(in consultation with your doctor)have your OGTT repeated approximately a month from the previous test.
Best wishes!

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