Working out

Before I got pregnant I did crossfit and ran, so I worked out around 4-5 days a week. I still continue to workout after getting pregnant, but my doctor told me not to let my heart rate go above 140 bpm. I find that impossible to do. I've seen videos of pregnant women still crossfitting/running and I can't imagine their heart rates are below 140.

When I workout I feel good, and I don't over push it. Plus I've read some articles that say the 140 thing isn't true anymore.

So my question is: Are any of you expectant moms still working out and going over 140 bpm, and everything is ok with the baby?