Abortion
Yeah... I know, I'm a guy, but don't use that to judge my opinions.
Anyways, I am not a Christian (I am a THEIST), but I can disporve Abortion AND Contraception using human logic.
The choice to contracept is a choice to PREVENT the handing on of human life when as far as one knows, that might otherwise take place. It is a choice to IMPEDE a certain life in a particular instance (the coming of an unwanted baby). This choice is against an instance of THE EIGTH MODE OF RESPONSIBILITY.
For those who do not know what this is, The Eigth Mode of Responsibility is One should not be moved by a stronger desire for one instance of an intelligible human good to act for it by choosing to DESTROY, DAMAGE, or IMPEDE some other instance of an intelligible human good (life).
Contraception is wrong.
BUT WHAT ABOUT ABORTION???? Well, same situation as listed above. You can not DESTROY, PREVENT, or IMPEDE something that is morally good.