Hi,
I believe that Judaism doesn't allow for abortion in rape and other cases
unless the mother's life is in danger. I don't remember what the final answer
is on when a life begins. However, there are specific laws involved and each
and every individual case is different in terms of how to deal with this
issue.
If someone is pregnant and spontaneously loses the "fetus" within a certain
period of time, then the law is different from when it happens later on in
the pregnancy in determining various issues such as a "first born" or etc. A
Rabbi has to be consulted in every single case since the final answer can be
different depending on the circumstances.
Hope this helps,
Dina