Nick, my point is that given the extremely high natural rate of embryos failing to survive, it is not reasonable to regard them in the same light as a born human. Embryos have no brain, no cognition, no pain receptors, in fact, very little to distinguish them from other fleshly parts of the mother's body. Even the fact that an embryo contains DNA from two individuals is not a unique circumstance, as there are people who have two sets of DNA in their cells (chimaerism), as a result of fetal absorbtion of a fraternal twin. I have read that research is now suggesting this is more common than previously thought.

I see an embryo as a potential baby, but I do not regard it in the same light as I do a born baby (or late term fetus), which has grown, developed a brain, and reacts to its environment. Embryos are a common product of unprotected human sexual intercourse. They seldom survive, which is a good thing or there's be sixty billion of us instead of six. Ridding oneself of an inconveniently timed embryo seems like common sense to me.

Other mammals have different methods of controlling fertility and thus population. Most large mammals are only capable of conceiving at one point in a year. Some small animals adsorb already viable foetuses if environmental conditions (overpopulation, food scarcity, etc.) make it unlikely they would survive. Mammals which have large litters will let one or more die by not feeding or abandoning the weakest. Humans have a multiplicity of weak embryos, most of which will not survive to term.

It is only now, with the understanding of human reproduction science has given us, that people like yourself have become so adamant about saving the embryonic. In Biblical times, a woman's foetus was not regarded as very important, worth only a small fine by law if destroyed as a byproduct of conflict. The church, for centuries, did not worry a lot about early abortions, and had varying views on the actual time of 'ensoulment'. It was only when a child was about to be born that any religious sentiment really crept in, at which point, of course, the woman was considered only a 'vessel' for the new soul, and often as not, if possible in a difficult birth, the child was saved and the mother let die.

Even the most adamntly opposed to abortion do not react emotionally to an early known miscarriage as they would to a stillborn or to an infant death (unless other circumstances, such as infertility affect their thinking). On some level they understand that it is not so important.