You should not try to lose weight when you are pregnant.
Idk your not supposed to lose weight in pregnancy. I mean sOme ppl get really sick and help it but you really shouldn't lose just to lose. You should talk to your doctor about it.
Unless your doctor advises that you lose some I don't see the point in worrying about it? After all you're going to be gaining being pregnant obviously. You can still maintain a good diet though, and it never hurt to exercise while pregnant! I've found swimming is awesome :)