Gestational diabetes but not overweight?!?

I have always wondered if I’m the only one who has had gestational diabetes even though you’re not overweight?? It’s always more prone for women who weigh a little more than they should but I was more on the smaller side. Anyone else not overweight and still has GD?? And does anyone know why this happens?!? I mean I know it’s because your hormones are different when pregnant and all that but it’s just annoying and i sometimes don’t even want to get pregnant because I always have to watch what I eat and can’t even enjoy my pregnancy like all the other women who can eat whatever do!