i thank you all for the responses especially Penna. I did not mean to impugn women who decide to make that terribly hard decision. I just mean that in my personal view there is no legal way that that which is going to be life is not itself life. Women don't get pregnant and give birth to anything but a living thing. that is why it was so hard for me and my girlfriend to even speak about that decision about a living thing that carried both of us within it. and when she lost it we felt the loss of a life not the loss of a potential one.
I think about him/her, my gf does too. we wonder what they would have been like, whose eyes they would have had, who they would have sounded like. i just don't see how this cannot be the loss of a life any different from another
Losing a pregnancy can be immensely traumatic and of course an abortion will be almost never harm free to the person getting it, but it is their choice to accept that harm as an alternative to carrying an unwanted foetus to term. When my wife and I were thinking of trying for another kid quite late in life (too late as it would happen) we carefully considered the possibility that a foetus with developmental problems might be the result and that we might have to choose abortion or to raise a severely handicapped child. As a biologist fertilisation is just another biological process to me. Cells are alive, sperm are alive, eggs are alive etc etc, so the moment of fertilisation isn't as special as many other people would hold, and my wife isn't religious either. However, we both recognised that any decision to abort would have emotional and physical consequences (for my wife) no matter what we logically knew. I guess what I'm saying is that when considering the legality of abortion we need to remove emotion as it doesn't help us reach sensible decisions particularly in this area.
Biology is used by all and sundry to try to justify their position on abortion and this to me is doomed to failure as there is no consensus amongst biologists, not even the atheist biologists.
Many religious arguments seem to say that as your DNA is unique you are a person from the moment a sperm and egg meet. By this measure the sperm and egg are also unique and I don't think anyone (barring possibly a few Christians who take the "spilling seed on the ground" thing literally) is proposing that a sperm or egg is a person with rights. So this argument is probably dead in the water from the beginning. Or should be.
Not to mention that lots of things can change the person that eventuates from that DNA before and after birth, from epigenetics (increasingly apparent that this is a huge factor) to direct things like drugs, alcohol, the woman's nutrition and nurture factors etc etc etc.
So even assuming life/personhood needs to involve DNA from an egg and a sperm, and not earlier, is the crucial point,
- fertilisation when DNA combines to form a new genome, leading to the 2 cell stage?
- implantation when you get a pregnancy?
- gastrulation (approx. 14 days) where you can no longer get twins or multiple individuals?
- when you can detect a heartbeat (approx week 6-7), as we sometimes classify death as when it stops?
- when you can detect brain activity (approx week 24-28), as we sometimes classify death as when it stops?
- during the perinatal period when a birth is possible?
- birth?
And even if you can decide on a criteria when a foetus starts to be a person/individual that doesn't answer the question of when the rights of the foetus equals that of the woman carrying them, as that is the point when abortion would not be allowed. Given that late term abortions are allowed in many places to protect the life of the woman carrying the foetus it suggest to me that it is fairly widely accepted that this point is very far into a pregnancy but that politically it isn't acceptable not to restrict abortion earlier under "normal" circumstances.
So not really a biological question IMO.
Edit: I also think that people confuse human being with human person. When a foetus qualifies as a human person is what we need to agree upon when drafting abortion legislaation.
