but nothing. you can be pro-choice and still a Christian. man's (United States') laws protect only born citizens of the country--not unborn and not partially born. abortion is legal because of this fact and to say the government should protect those who aren't even citizens would be ridiculous--hey, let's give illegal aliens and others with fake identities benefits and protections too! as far as the law goes, there's not much you can do to change it, and even if abortion became a states' rights issue you still wouldn't be able to stop it. as a citizen, you're pro-choice by default because people will kill their babies no matter what the laws are.
as a Christian, though, it is your moral obligation to try your darnedest to talk somebody out of getting one. babies are the purest image of G-d available and you have to protect them! even in the unlikely event that a woman was impregnated by rape, you should talk them out of it, because why should a baby have to suffer because its mother didn't go to the hospital and get the standard rape kit? why should the child have to suffer because its dad's a monster?