Your boss must check with the salon's insurers. Although I do massage and have done pregnant ladies after 1st trimester, I do not do pregnancy massage. I work on neck, shoulders and back while in seated position. The only way I would be insured to do pregnancy massage is if I took a course with an accredited trainer and then sent in my certificate. Training by other members of staff will not suffice for insurance purposes and it would be your boss who would be responsible. You could ask her/him to write down that it is their decision that you will do pregnancy massage without undertaking formal training with qualification and they take full responsibility. Although your boss will probably not agree to do this, it might make her/him think a bit more.