I am 5'4" and was 73kg pre-preg and felt a little overweight. During the pregnancy, I maintained my weight until around 7 months when I went up to 76kg ... I'm now around 75kg and am working to get back to 70kg then to 65kg. I also had pelvic instability during the pregnancy and although I didn't put on weight, I lost fitness. First pregnancy I didn't actually put on any weight and I didn't have the pelvic instability and maintained my fitness. As Onyx said, it's what you feel. I have friends the same height as me who are very comfortable at the same weight as I.

Good luck!!!!!