Actually with diabetes carbs are def something they have you limit. That is because carbs turn into glucose and since your body isn't disposing of glucose as it should, it transfers to the baby. This can cause abnormal weight gain for them which can cause complications at birth and later in life. But a very well balanced diet filled with lots of protein and good carbs and all should be well! I know bc I have diabetes and this is my 2nd pregnancy. My first was born 38 weeks at 7 lbs 9 oz and the second is measuring right on track at 35 weeks. Its hard limiting yourself in the beginning but you will start feeling healthier bc of the change in diet and most importantly remember it's not just for you, it's for your child as well
I haven't had it as far as I know, but since I have never been tested for it, my midwife told me how to balance out nutrition. You don't have to stay away from carbs. You just need to make sure you balance the carbs with protein. So if you eat a baked potato, be sure to add cheese and other protein filled things to keep that balance.
One of my favorite things to make is fried potatoes with cheese, eggs, and turkey bacon (since I don't care for pig bacon). I slice up a potato and put it in a skillet with either butter or oil and I let it brown, meanwhile I cook the bacon. As soon as the potatoes are done I add seasonings and crack the egg and add it straight to the potatoes. I mix it up and let it cook. Then I add in the cheese and turkey bacon. Since it is one of my favorite things, I asked specifically about it and my midwife told me that with the eggs, cheese, and bacon with the potato made it just fine. Of course you still want to eat fruits and veggies, but just because you have gd doesn't mean you can't eat what you like.
They didn't catch mine until 31 weeks with my first. I was induced at 39+5 because they thought he was 9lbs. He was 8-6. He's now a healthy 18 month old. 75th %ile on height, 35th %ile on weight. Follow a low carb diet (it's hard, but you can do it!) And you'll both be just fine!