Just a thought guys,

I think the reason why you cant use foot spas is because the jet streams concentrate on specific points on the bottom of your feet to relax you. Some of these points actually induce labour or can cause miscarrage so you have to be careful there is no pressure on these points. I guess it is a safety thing for them. Just be aware of the pressure points on the bottom of your feet which are not supposed to be massaged during pregnancy.

I think a reflexologist or acupuncturist will be able to clarify in more depth about this.