I have a bit of a strange position, in that I'm Christian and generally anti abortion but think that abortions should be available if needed. I believe that the pro-life groups that think they are basing their anti abortion stance on the Bible are simply wrong (or at least over egging the pudding). All of the statements in the Bible that can be interpreted as anti abortion are indirect.

Here's one statement that's relatively direct in Exodus 21:22-23:

"If men who are fighting hit a pregnant woman and she gives birth prematurely but there is no serious injury [i.e., to the mother], the offender must be fined whatever the woman's husband demands and the court allows. But if there is serious injury [i.e., to the mother], you are to take life for life, eye for eye, tooth for tooth, hand for hand, foot for foot…"

Here we have a reference to the causing of miscarriage by violence. It clearly does not place the value of embryonic life as the same as the life of the woman. Therefore, according to Exodus, the causing of miscarriage (indirect abortion) is bad but is not murder. You could say it's an accident, I suppose, therefore dealing with manslaughter rather than murder. But I think the implication is that the foetus isn't considered to be fully human.

When looking at biology I find things a little more difficult. As far as I can see there are two possible times for a definite start to human life. These are conception and birth. We know that babies can survive prematurely. I'm convinced that treatment for premature babies will improve and survival prospects will get better for people born prematurely. The criteria for when a fetus is 'viable' will continue to change. This leaves me believing that conception is the real definite starting point for human life. As a result I don't like the idea of abortion and would hope that people would choose otherwise. I would hope that people are given every other viable option to consider in addition to (and in preference over) abortion. In reality it would be stupid to ban it as backstreet abortions would increase dramatically and we'd see a lot of mothers dying again as a result