When one has sex willingly they are accepting the possibility that she can become impregnated. In the case of rape that person has been traumatized and was violated. That person shouldn't have to go through carrying a child in her body for 9 months and then going through the pain of birth to a child. A child that is the everlasting memory of the night she was violated. In the case of rape and incest I'm pro-choice, otherwise no.
In both cases 100 lives were taken, but a person would react more intensely if the egg was more developed and more human-like. That is psychological.