You may not have been expecting any males to check in on this topic, but I just saw a news segment on TV about how doctors are more likely to encourage exercise during pregnancy than they were in the past.
In my opinion, though, the rise and fall of the waltz and the hip action of other dances wouldn't be conducive to your current situation.
But here's something to look forward to: This particular news segment also focused on how women who, prior to their pregnancy, were active in some form of sport or recreation, found that they came back stronger after the birth of their child. The premise was that the endurance and the strength built up over carrying and delivering a child would equate to a stronger body and better performance.
A woman who was rather sedentary prior to becoming pregnant obviously wouldn't benefit from this theory. But a dancer sure would.
You'll be back at it, and probably better than ever, soon enough.