You shouldn't go on a diet during pregnancy but you certainly can monitor calories and eat right. Good protein is filling. Just eat a clean diet with lots of vegis and fruits. Exercise! Ask your doctor if it is alright, and it should be, if you can start walking, lifting light arm weights, or as mentioned, some of the work outs created for pregnant women. This will help you feel toned.
But it is hard. I gained a lot of weight as I had my boys back to back. Didn't like it. But it does come off. It will be okay. hugs
The best thing you can do is eat healthy and stay active during pregnancy. Sometimes our cravings get the better of us. Eat a well balanced diet, not too much sugar, sodas, fast food. And walk 30 minutes a day unless medical reasons prevent it such as bed rest, pelvic rest, etc. Also check in with your Dr about weight concerns. they may be able to recommend a nutritionist or diet for you :)
they sell exercise videos for pregnant women