It's totally possible to continue doing low-carb while pregnant, however if you are struck with really bad nausea/morning sickness then you'll probably have to stray for at least awhile (you still need to eat SOMETHING ). Still, you may or may not stick with it. As far as gaining, I strongly believe that every woman's body is different and is going to do what it needs to do while pregnant. Sure, you could easily gain way more than you should by eating a TON, but sometimes even when you eat healthy and don't overdo it, you'll still gain like 40+ pounds. To an extent you'll just have to accept it and let your body do what it needs.

I'm currently 30 weeks pregnant and have only gained 18-19 lbs, which I'm really excited about (I've always been an easy gainer, but my metabolism is through the roof right now). I eat pretty healthy, but not super low-carb. I'd estimate that most days I eat around 150-175 g net carbs, though I'm sure I have some higher and some lower days... I planned on eating no more than 100 net carbs, but I've been so hungry that I just can't seem to keep that up. That said, I have friends who eat pretty much as I do and have stayed active, but have gained a lot more than me. It's not because they're overeating or not exercising, it's because their body is doing what it needs to to have a healthy pregnancy...

Long story short, just stay as healthy as you can and try not to worry about it too much. You'll probably focus more on the weight in the beginning, but once you're a ways along you kind of let it go. A healthy baby is the most important thing.

Good luck with everything!!!!!