I agree that birth is another one of the major turning points in pregnancy. It is easy to put forward birth or conception as special. There are certainly problems with conception being the start of personhood, but the problem of birth being the start of personhood is that someone could be born premature. They are obviously a person when the come out premature, but if they had been born later, then under the theory you put forth, they wouldn't be a person until later. I think that many people believe that personhood is connected to something about the baby/fetus, not the location of it at any given time.

In regard to the idea that a baby is a parasite: I think that, contrary to what Sarah said, we DO have a moral obligation to help people in need unless doing so would hurt us more than they are hurt now. The fact that most people don’t do this is no excuse. Also, I feel that parents have an especially strong ethical requirement to care for their children which would make late term abortion especially wrong.

(notice how religion is not needed for this argument at all)

"Principle of Double Effect... the woman's life is to be saved in ectopic pregnancy, but by a means that does not include direct abortion of the child."
That's theological nitpicking to get around a theological conclusion. "We can't suck the embryo out of the tube that it will eventually rupture, causing you to bleed out and potentially die if you don't happen to be in close proximity to a hospital at the time, but we can wait for it to do that, then cut out the torn tube, which just happens to contain an embryo."

The woman's life is recognized just as much as the child's in the principle of double effect, and in the case of ectopic pregnancy, the woman's life is the one that can be saved and the one that receives direct effort to save... Principle of Double Effect... the woman's life is to be saved in ectopic pregnancy, but by a means that does not include direct abortion of the child.

This is silly. Whether or not an intermediary exists between an action and a result doesn't reduce the moral weight of the decision being made. Isn't it your own Bible that declares, "By the fruit shall ye know the tree"?

What you are doing is twisting desperately to avoid what you clearly see as a contradiction in your espoused morality and the practical effects it has.

Sarah is right. This is nothing more than the continued policy of the Catholic heirarchy to subjugate women, and is yet another blot on their record.

Further to the logical problems noted above, an interesting illustration of the problems of carrying the battle "backwards" (in the human embryological development sense) in legal terms here. Irish constitutional law does vigourously protect the life of the "unborn" with the effect of forbidding 99.99% of abortions (legal definitions even here are tricky things). But the case above concerned a separated couple's disagreement about the fate of frozen embryos produced from their respective egg and sperm prior to their separation. The woman argued - unsuccessfully - that the embryos came under the heading of "unborn" and had a right to be implanted and carried to term, whereas the man argued - successfully - that the unimplanted embryos did not satisfy the criteria to be protected as "unborn," and moreover, that he had the right not to become a father against his will. His argument having carried the day indicates where Irish women need to focus our energies in proposing liberalisation of our own abortion laws - we can now assert that there is a legal precedent in favour of the principle that people cannot be forced to become parents against their will.

although a casual googling shows Catholics

Please do not get information on Catholic teaching from wikipedia, CNN, googling, etc. Church teaching is regularly misrepresented by modern media sources. Go to official Church documents, or the Catechism of the Catholic Church.
http://www.scborromeo.org/ccc.htm

when you vote for a party that denies socialized medicine you indirectly cause the deaths of hundreds of people who would otherwise have been saved.

The big word here is indirectly. To indirectly impact someone in a negative way, which would likely be undesired, is not the same as a choice to make a direct, desired action toward someone to end their life.
Regarding the death penalty, you bring up a good point. There are Christians who think the death penalty is okay, which is contrary to Catholic teaching. The Church teaches a consistent ethic on life, and all Christians ought to uphold that, which certainly includes being against the death penalty.

This can only mean you favor letting the woman die, since that is what will occur without an abortion.

This is a false statement. The woman's life is recognized just as much as the child's in the principle of double effect, and in the case of ectopic pregnancy, the woman's life is the one that can be saved and the one that receives direct effort to save... Principle of Double Effect... the woman's life is to be saved in ectopic pregnancy, but by a means that does not include direct abortion of the child.

In fact, the Church upholds human life as so sacred, that it must be protected from its very beginning to its very end.

Unless the life in question is that of a woman with an ectopic pregnancy, in which case you said specifically that you were against abortion. This can only mean you favor letting the woman die, since that is what will occur without an abortion.