August 2, 2000
Gestational Diabetes, Type 2
Question from Atlanta, Georgia, USA:
I am a 32 year old female who is five feet nine inches tall. My pre-pregnancy weight was 134 pounds (underweight). In the first two months of pregnancy, I lost four pounds without morning sickness. Now at 29 weeks, my weight is 148 pounds. Yesterday, my one-hour non-fasting glucose test came back 312 mg/dl (17.3 mmol/L). However, I had nothing oral before (4 hours) or after drinking 50-gram glucose solution. I am scheduled for a three-hour glucose test tomorrow. My concern relates to such a high count. All information I have read shows people with numbers considerably lower than this having gestational diabetes. As this would seem to indicate that gestational diabetes is indeed to be the expected result of the three-hour test, how likely is it that this is strictly gestational? Would diet be a consideration for me? What can I expect with such a high reading ?
I am also concerned with the lack of information about type 2 diabetes for underweight women. Most information seems to rely heavily on a woman being overweight. My weight has always been considerably underweight (120 pounds until 3 years ago). Can you recommend a book or other source of information that might cover this aspect?
A one hour glucose test over 185mg/dl (10.3 mmol/L) is practically diagnostic of gestational diabetes. Unless there was some laboratory error, then your three-hour test will most likely be abnormal. Being overweight does increase the risk of gestational diabetes. However, even thin women can develop this problem since it is mostly due to hormones produced during pregnancy. You may want to talk to your physician about checking a hemoglobin A1c to determine if you have had long standing hyperglycemia. It is possible you may have diabetes even when you are not pregnant, and it is important to rule this out. Diet may work for you, but insulin may be required during this pregnancy. Your physician should have literature for you about diabetes or you can write or call the American Diabetes Association.