Hmmm, it is pretty clear, Skeptic2, that the article linked to was not of a scientific nature. It had a clear agenda against abortion, and, carefully reasserting that I seek to make no comment here on my views on that particular debate, it was also very clear to me that it was of the type of thing that seeks to clothe itself in an air of scientific rigour that it didn’t actually live up to.
So, for sure, you could have a scientific discussion about when exactly an individual human life begins. It seems to me that, if it was to be a really serious discussion, it might take Tibor Gánti’s chemoton as a model. I remember being involved in a discussion about whether a sperm should be regarded as ‘living’, not just because it is motile, but because it metabolises. We certainly talk about sperm dying. But if it does live, then what is it? Human? And in point of fact, why constrain the discussion to the matter of when life begins? Death too has become a more nebulous concept. Certainly, we may point to someone who is clearly living and someone else who is clearly dead, but the precise moment of transition from one to the other is not just as free from matters of interpretation as it once seemed.
But it is very clear, if the discussion is to be purely scientific then never at any point should it include discussion of the rights and wrongs of abortion. I strongly suspect that precluding that would preclude the interest of the OP.