Here's an alternate approach (more of a fundamentalist approach, and probably not what you are looking for):

God chose that woman to allow the sperm and egg to unite and become a fetus. So then why does she have the right to go against God's actions? Quite often a woman and man can have sex at her fertile time of the month w/o any contraceptions and still not conceive. It's not as simple as most may thing. Some people can almost look to it as an "miracle of God" that everything happened as such that the embryo was allowed to start forming.

So that's pretty extreme, but I'm just playing "devil's advocate" here. I'm sure it's not what you were looking for, so here's my more sane argument:

Personally, I have a hard time with the way fetus is defined there: "a fetus is not a human being -- it is a potential human being, i.e. it is part of the woman."

Webster's defines it as: In humans, the unborn young from the end of the eighth week after conception to the moment of birth, as distinguished from the earlier embryo.

According to Capitalism.org's definition, it would then be ok to terminate a pregnancy up to the day before the child is born because "it is not yet human". I can't agree with that. Many fetuses have been known to be able to survive during the last 3ish months of that term. My latest was born 5 weeks early, with no complications (unless you count jaundice) but yet according to them, I would have been able to abort him within those five weeks (had he kept put) w/o it being considered murder.