I started with a healthy weight. Midwife has never really bothered to weight me and the only time they did was at 12 weeks. Since then I've gained 3-4 kg. (the total is just estimation because I did get chubby in the first trimester but gradually "slimmed down").
I never go hungry, so surely I should be ok? With my first I gained 15kg total but I was already overweight.