Past life regression has become a craze in Mumba due to the popularity of books by Brian Weiss. Some people claim to be trained by him even though they've attended a two day workshop for self-regression with hundred of other people.
While it is possible to regress to what appears to be a past life, most people only regress to symbolic experience that resembles a true past life experience.
In a true regression to a past life the suject shoulld be able to remember details that can be verified i.e the currency used in that era, names of rulers and other historical details.
A false regression is more dream like and the information is of a symbolic nature. There are dangers of uncritically accepting such information and therefore one must be careful about who one allows to play with your mind.
While it is possible toenter into various altered states of conciousness; they including regressions and future progressions can be used therapeutically.
There are many practitioners of past life therapy including some who call themselves "the best past life regression therapist in Mumbai" who seem to offer this therapy as a cure all for all types of problems. Imagine if your doctor was to prescribe asprin for every ailment that you suffer?
Often one first needs to attend to problems of this life before those of past lives. If past life issues emerge spontaneously in regression sessions then they can be used to resolve issues symbolically.
Recreational past life regressions could be hazardous and in many cases lead to relationship problems or identity confusion especially if not done by a well trained hypnotherapist.