Birth is a matter of chance because no one chooses where, when, or in what kind of environment they are born, whether it be familial, cultural, or national.
Some people believe in reincarnation, while others think that everything has a purpose and that’s why we are born at the perfect time and place.
I can respect that, but as an agnostic, I find it hard to believe, though I can't prove otherwise either.
However, what I do believe is that we must do something with that chance.
Birth is a matter of chance, living is our choice.