The biggest lesson I've learned from tightly managing blood glucose levels during my one and half pregnancies, is the benefit of eating a lower carbohydrate diet.  I actually enjoy having a set carb limit at each meal because it helps me to make smarter food choices and keeps my blood sugar levels much more manageable.  I suppose it is simple logic that fewer carbohydrates require less insulin, and the more moderate your insulin needs the less likely you are to miscalculate your insulin...