Hi! I've been doing CrossFit for about a year and a half. I am 8 weeks pregnant and still workout 4x/week.
I scale the weight I use, and I NEVER try to PR anything...ever. I told my coach I was pregnant before I told my mom (lol) because it was important that she know immediately so that we could work together to avoid injury. Now that she knows, she doesn't have me climb the full height of the rope (for example), and as my pregnancy progresses we will be finding alternatives for other exercises, like burpees and handstand push-ups (which make me feel like I'm going to vomit).
I usually get a bit nauseous every time I work out, but I excuse myself for some air/water if I need to and then jump right back into the workout when I can.
I think the most important part is to listen to your body and remember that you aren't there to win any medals. I'm proud of you for working out - it will make everything about pregnancy SO much better!! I didn't do ANYTHING when I was pregnant with #1 and I gained SOOOOOOO much unnecessary weight. Go, you!