February 16, 2002
Gestational Diabetes
Question from Lexington, Ohio, USA:
I am a 31 year old Caucasian with no family history of diabetes, and I am not considered overweight. Two years ago, during my last pregnancy, I had gestational diabetes treated with insulin. I am currently seven weeks pregnant, and my blood sugars are already running high. I’m having trouble finding research that mentions how high they can get before worrying about birth defects, miscarriage, etc. during the first trimester. My fasting levels are on average 92 -106 mg/dl [5.1-5.9 mmol/L], and my one-hour after meal sugar has been up in the 160s mg/dl [8.9 mmol/L] on a few occasions. A two-hour glucose tolerance test at six weeks postpartum and a fasting blood sugar one year later were within the normal range, though they were borderline-high. I had one unexplained miscarriage in three years ago in my tenth week.
Answer:
It is possible that you have had some degree of glucose intolerance between pregnancies, perhaps bordering on type 2 diabetes. Checking a hemoglobin A1c value would be helpful.
Your doctor should be addressing these elevations in blood glucose with diet and possibly insulin. An alternative would be glyburide [a pill for Type 2 diabetes] (an oral hypoglycemic agent) once you are out of the first trimester.
Any persistent elevation in blood sugar in the first trimester places the fetus at risk for abnormalities. The higher and more prolonged the elevation, the greater the risk. Therefore, you should be scheduled for some ultrasound examinations for general development and also of the fetal heart.
OWJ
