As is usually the case, I once again find myself agreeing with a position expressed by Amy at The Fifty Minute Hour: "...even if I believed that carrying human DNA granted a being the right to life, which I don't, that doesn't guarantee that being the right to live in my womb for nine months. Now, perhaps a pregnant woman should turn to her stomach and ask the fetus nicely to get out before seeking an abortion, but the point is that as long as a fetus lives inside of an independent, thinking, feeling person, the person's right to control the course of her own destiny trumps any claim the fetus might have to a right to life."
Nothing has a political right to be a parasite not even a genotypic human. This is also a pretty good argument against tax-funded welfare. Without choice, you don't have charity. You have theft and slavery. But perhaps I'm being too blunt again.