One problem in all of this is defining when a fetus acquires a separate life. Most people would say that a crime has been committed if you could abort a fetus one day before delivery date.
That has its own philosphical integrity, but if you think life begins precisely at conception, then you gain a different set of problems. Often, a newly-fertilized egg gets sloughed off or fails to implant, etc. But nobody says funeral masses or purchases cemetery plots when a woman trying to get pregnant has an unusually heavy period.
So: where to draw the line? In the States, Roe v. Wade actually does a decent job IMO. It's been taken as an avatar of pro-choice policy by both sides of the debate, but what it does effectively say is that only the first trimester is solely the woman's business. Third trimester abortions can more easily restricted, and the second term is more up for grabs.