We are born on Earth to settle our give-and-take account or Karma and do spiritual practice. Spiritual practice can be done on Earth plane with most success. In the Nether world and Hell it is almost impossible to do spiritual practice so as to burn our give-and-take account (Karma).

Where are we before we are born?

After we die on Earth, we (i.e. our respective subtle bodies) go to one of the various subtle regions of the Universe depending on our spiritual level and our merits and sins. Here we stay for varied periods of time before we get a chance to be born back on Earth.
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Life on the Earth region is of great importance as it is the only plane where people from the lower regions can be born to do spiritual practice, complete their give-and-take account (Karma) and get outside the cycle of birth and death to achieve permanent Blissful existence.

How many births have we gone through?

It is very difficult to give an answer that will encompass all people. The thing is we could have lived over a thousand births as humans and it could also be the first time we are being born in this current lifetime of ours. However on average the person at the 20% spiritual level in today’s’ world would have been born a number of times in the last 1000 years.