I'm a hypnotherapist, amongst other things. When I first qualified, I asked a Tibetan teacher what he thought about 'past life regression' and if he thought I should offer it to clients. His reply was "People can make things up" and that he didn't think it was a good idea. There's also something called cryptomnesia which can come into action in so-called regression cases. (stored present life memories of all kinds, even down to magazine articles, photos, movies etc) Personally I have no interest in speculation about past or future lives