I was 260 lbs when I got pregnant, and I got over 300 with the pregnancy...though 15 of that was water retention. Within 2 months of giving birth I was back down to about 265. The worst part for me was just adding to the too much weight I already carried. I ached a LOT during the pregnancy.
She needs good pre-natal care!
And what Scorbett said... don't give into cravings. Gaining too much weight when already obese can make everything so much worse. And get off IP phase one immediately.