Some people who had gestational diabetes also end up with Type 1 diabetes (adult onset).
Do not be shy to use insulin during pregnancy. Most important is to control blood sugars very well for both mother and baby to have best possible outcome.
Reduce carbs, exercise, monitor blood sugar closely during pregnancy.
That is gestational diabetes. When you get pregnant, all kinds of hormones and things get working a bit differently. Some people end up with Type 2 after experiencing gestational diabetes and some don't. What's important is, drink plenty of water, get exercise, watch your carbs and pay attention to your health for the sake of your baby.