I am pro-life, but this is honestly one of the weakest possible arguments for a pro-choice person to take. The fact of the matter is that situation is EXTREMELY unlikely. The number of pregnancies as a result of rape in cases of abortion is very, very low. I feel that if someone was raped, that it is a little more respectable to choose abortion. It becomes even less of an effective argument if you believe in the morning after pill, in which case it offers a chance to prevent the likelyhood of having a child even more.
In the US about 1% of abortions are done because of rape or incest.
1.4 million abortions are performed in the US each year.
That's 14,000/yr as a result of rape or incest.... Doesn't sound EXTREMELY unlikely to me.
Since you are pro-life, let me ask you a question. What is your solution? Adoption, forced abstinence, ???