For me it is simple. Pro-life is support for life at any time on the spectrum of life. This would include the obvious things like abortion and capital punishment but should also include things like torture, poverty, lack of affordable health care, nutrition, war, and other things that diminish the divine spark of the image and likeness of God.
Fr. Z has a discussion going on over on his blog about this very subject. Surf on over and join in the conversation.