I am in my 28th week of pregnancy, was diagnosed with gestational diabetes in my fifth month, and I have been on twice daily insulin. for the last 10 days. My fasting blood sugars have been around 125 mg/dl [6.9 mmol/L], and my two-hour after meal blood sugars are never under 140 mg/dl [7.8 mmol/L] but often rise to 160 mg/dl [8.8 mmol/L]. I am panicking and depressed about these numbers as I am trying to be strict with my diet and exercise. My doctor is increasing insulin by 2 units every third day, but the readings are the same. I have several questions:

Are sustained readings like this over 10 days risky to my baby?
Is it common to have such high fluctuations with gestational diabetes
How long each daily should someone with are gestational diabetes exercise?
Should exercise be done after eating or before?
At what stage would a doctor know whether a patient with gestational diabetes needs a C-section or induction?
What are the chances I will have normal vaginal delivery?

The risk to the baby of sustained elevations in blood sugar values is excessive growth. Your blood sugar values are higher than I would like, but not terrible. Unfortunately, even a mild elevation in blood glucose can result in a large baby.

The other downside is that the baby is at risk for neonatal hypoglycemia. The reason this happens is that the baby is used to receiving lots of sugar from you during the pregnancy and thus produces more insulin. After delivery, the excess sugar load is gone but the baby is still releasing the same amount of insulin which causes a drop in blood glucose. The pediatricians are aware of the situation and are prepared to treat the baby until its pancreas adjusts to a new level of insulin production.

Exercise is not going to help much in controlling your blood sugar. There are no guidelines for exercise during pregnancy as part of control for gestational diabetes. You need more insulin. Raising the dose by only two units is not adequate. I would suggest taking to your doctor about being more aggressive in increasing your insulin dose.

If your baby is getting too big (usually based on ultrasound measurements), then your doctor may consider either early induction (with documentation of lung maturity) or just going to a cesarean section. Doing a cesarean section outright is uncommon, and most doctors will opt for labor first. I cannot promise anything, but from what you say, you stand a good chance of having a successful vaginal delivery.

OWJ