This is going to seem like an ad hominem and I assure you that it is not: You do not matter in a situation such as this. You say that you would rather raise the child, but you give no thought to what a woman must go through in order to bring a child to term, how it affects their lives, their minds, their livelihoods, etc. You are making your feelings paramount, while simultaneously acting as though pregnancy is a minor affair. There are women out there who simply do not want to have children for whatever reason and a man should not stand between them and that decision precisely because of the degree of labor involved solely on the part of the woman.
And, to make it more personal, I was in a situation in which a former girlfriend was pregnant. She asked me what we should do and I told her that it isn't a matter of "we", it is her that must bear the burden of pregnancy and that I, because I am a man, can only operate in a supporting role for whatever decision she makes.