I understand you have been told why is it so important for you to control the sugar levels. It is the post meal glucose excursions that will determine whether or not your baby is going to grow bigger than normal which is the usual case in women with gestational diabetes Hence you need to ensure that glucose does not rise more than 140 mg/dl in an hour of taking your meal and also fasting ( before breakfast) should not rise more than 100 . You can check your sugar levels at home and more number of times you do in a day the better it will be for you.