Hun TBH that sounds kinda crazy to me. I've never ever heard of fluid restriction and I would be really cautious of it. Some ladies just put on more weight. I don't eat much more when pregnant, exercise and live a healthy lifestyle and each time I've put on at least 20kgs. There is nothing I can do to prevent it, it's just the way my body is when pregnant. I'd seriously consider ignoring her advice, as I said it sounds extreme and I'd think dangerous. Make sure you eat plenty of heathy fruits, vegetables, lean protein and wholegrains. Drink lots of water gentle exercise and if you pit on weight then so be it.

HTH
Spring xx