Ah, the quintessential recurring unsolvable debate; what we have here ladies and gentlemen is two paradigms. The arguments of relevance for one are irrelevant to the other and vice-verse.
But I find the following points of interest even if others don't.
Firstly, saying 'prostitution and drug use are illegal; therefore restriction of a person's freedom of action with their own body is okay' is not a good argument; it assumes that drugs and prostitution being illegal is right, when this is certainly open to much argument.
Secondly, the Bible does not outlaw abortion; not once, no where. Despite there being a separate word for it, despite abortion being a known practise in Biblical times, the word is not used and whilst boiling baby goats in their mother's milk and wearing a fringe round your garments does get into the Mosaic Law, abortion does not. Please prove me wrong. But to start, think about the word for a living soul in Hebrew and how this cannot apply to the unborn.
Thirdly, if a fetus representative of the average abortion in a well-ordered medical system is a person, then so is small rodent. Small rodents and first trimester fetuses have equivalent levels of neurological complexity. Do some research on brain weights. Of course, if you believe some divine spark enters the egg on conception then you are pushing a religious argument of no value in secular society and may as well start handing out head-scarves.
Fourthly, if 'human potential' is so important (as small rodents will always be small rodents but a percentage of fertilised human ova would one day be born if they weren't aborted), then why do anti-choicers not show the same level of concern to the children of the poor whose human potential is being cast aside? Why is it right to stop a woman getting an abortion yet okay to support political policies that condemn many children to gross disadvantage?
Fifth; between 40 and 60% of conceived eggs spontaneously abort before the mother is aware she is pregnant. Anti-choicers apparently hold the blastocyst or far greater import than 'mother nature'.
Sixth; many animals spontaneously abort if conditions are not right for giving birth. Humans certainly can't d this naturally, but then there are lots of things that humans cannot do naturally that they do everyday, so why should a human aborting if conditions are not right for giving birth be so wrong?
Seven; if killing people is wrong, why is killing unborn 'people' 2.5 cm long okay, but killing people by judicial execution okay? It's not like the death penalty has never killed innocent people.
Eight; great apes and dolphins have intellectual and emotional complexity approaching that of humans, and way way more than that of even a second term fetus. Why is it okay to kill them?
Nine; I firmly believe if human fetuses looked like lizards, no one would give a $hit. The fact they look like tiny humans is what skews the debate. Yet people see the (if we are talking about fetuses or embryos of an age where abortion would normally take place) apparently human appearance yet fail to consider the already made point about neurological complexity.
Ten; if you don't like abortion, don't have one.