January 4, 2005
Gestational Diabetes, Hypoglycemia
Question from Israel/ Rego Park, New York:
I am a 38 year old female who was diagnosed with acute hypoglycemia approximately 30 years ago. I am in the 36th week of my fifth pregnancy. I recently took the three hour OGTT and the values do not make sense. The fasting level was 128 mg/dL [7.1 mmol/L]; after one hour, it was 73 mg/dL [4.1 mmol/L]; after two hours, it was 110 mg/dL [6.1 mmol/L]; and after three hours, it was 50 mg/dL [2.8 mmol/L]. It would only make sense to me if the first two vials were inadvertently switched.
Could I have gestational diabetes if my system broke down the glucose all the way to 50 mg/dL, which it did during a previous pregnancy, and fit in with my hypoglycemia? Is it possible that the glucose level increased from 73 mg/dL [4.1 mmol/L] after one hour to 110 mg/dL [6.1 mmol/L] after two hours if I did not ingest anything, except for small amounts of water to prevent dehydration?
Answer:
I have seen some odd results on the three hour glucose test, but not one where the fasting was the highest value. I have seen results where successive readings showed a slight increase, but it would come down by three hours. The high fasting value is concerning, but does not make a diagnosis of gestational diabetes, particularly since all the other values were normal. At a minimum, I would suggest repeating a fasting glucose and you may want to consider repeating the entire three hour test.
OWJ
