I did an aromatherpy message on-board when I was 14 weeks pregnant. It wasn't really obvious yet so I did let the spa attendant know and wrote it on my health form when I checked in to the spa. She used extra pillows that I was able to position to be more comfortable, and there were certain oils that she would not use, but others were OK - she knew which were not an option. I found them to be very professional and knowledgable about it.