I had a gym instructor who keep taking classes right through her pregnancy.... but then of course she was used to all the exercise.
In regards to weight gain.... I still have a couple of weeks to go but in regards to my pre pregnancy weight I lost 2 kg and now slowly starting to put it back on. I am still under the pre pregnancy weight. I was told that this can be normal too!!! There is so much that could be normal I guess we shouldn't be too concerned about how much we gain or lose, unless of course it is excessive!