Politically correct label that applies to people who oppose a woman's right to chose. The choice of words, 'pro-life', suggests that the people who don't agree with them are 'pro-death' and therefore bloodthirsty babykillers.
Using the 'pro-life' label allows those who are described by it to do the following:
-Avoid any rational debate
-Advocate the murder of doctors who perform abortions
-Walk around with pictures of dead babies
-Never have to point out that they have never been in a predicament that would have them consider abortion (extreme poverty, rape...)
-Live in a fantasy world where abortionist kill babies as a hobby in satanic rituals
-Speak God's name in vain
-Hello, I'm Michael, 'I'm pro-life'.
-Really? well that's nice, death sure is overrated.
-Wanna look at my pictures of mutilated babies?