So I kept up with my running schedule (with lower intensity/distance) until the end of my 2nd trimester (around week 27). At that point I started to get side aches and would have to slow to a walk. I wasn't even running that fast, just jogging and plodding along. I was hoping to run longer into pregnancy, but oh well. Being in good shape before and during pregnancy and having strong abdominals has made it so that I haven't had any lower back pain. I think having good posture has helped too.
After I stopped running I was planning on walking for exercise or going to a gym to use their machines if walking didn't do enough. Unfortunately I got really sick right after I quit running and that lasted for 2 months. I am finally well enough now to expend energy on exercise and so am wanting to start up again with something.
I am planning on running a half-marathon next summer sometime. I think I need a goal like that to help myself get back into the running habit and get back into shape. I am really excited to use the running stroller I purchased. I got it used and at a discount (yay!). It also has an awesome name: THE IRONMAN.