I think the point is that I'm pro-life, I'm just "proer"-choice.
Obviously situations where the mother's life is in danger are kind of a gray area, but I think you could comfortably be "proer"-life and oppose the choice in non-life-threatening situations. Not that I agree, but that opinion wouldn't be "anti-choice".
And most of the pro-life positions people take are also pro-choice, just to a lesser extent than they are pro-life.
Choosing what you perceive to be the lesser of two evils doesn't make you pro-evil;
choosing what you perceive to be the greater of two goods doesn't make you anti-{life,choice}.
EDIT: To further clarify, I'm not at all confused as to what camp I'm in. By standard definitions, I'm definitely pro-choice. The point I'm making is that the standard definitions are not hugely useful.
It's the same sort of weasel words that Creationists use to confuse Christians who can accept science but now think it runs counter to the idea of "God's Creation".
Obviously situations where the mother's life is in danger are kind of a gray area, but I think you could comfortably be "proer"-life and oppose the choice in non-life-threatening situations. Not that I agree, but that opinion wouldn't be "anti-choice".