As long as you are fit & well then it is safe to use them but only in small time frames. Eg 5 minutes at a time.
If you are unsure check with your own GP / MW as they have access to yu notes etc & can make a clinical decision.
The gym is fine too as long as you have a personalised work out plan.
Aqua natal aerobics is a really good way to keep fit when pregnant as the weight of the bump is supported by the water.
Hope this helps.
Every Woman is entitled to understand what happened in her pregnancy when pre eclampsia strikes. I hope to be able to support that process.