Hot baths and pregnancy

So I read something that said that taking hot baths for long durations messes up blood flow and can dehydrate you, and it’s worse when pregnant which can lead to vomiting and dizziness.

Which is what happened to me exactly, when yesterday night I took a long hot bath and the morning of, I was throwing up and I thought I had morning sickness.

Not to mention this happened to me long ago when I took a hot bath, walked in the heat and threw up hours later. I think that had to do with dehydration.

Is this a real thing and has it ever happened to anyone?