Secular reasons for and against legalising abortion

[FatAndFaithless]

I heard in an audio book about statistics that it's possible that abortion reduces the crime rate, I only have 3 minutes to think about what I'm typing here which is frustrating but it's in an audiobook called freakanomics and it's basically saying abortion stops unwanted babies which turn into unwanted children who basically know they are unwanted and hold a lot of resentment and so on.

I remember that chapter. I believe the conclusion wasn't quite as simple as "abortion reduces criminals", but rather that areas that encourage pro-choice ideas also happen to have healthier ideas about other things such as gender roles (woman =/= mother by rule) and economic disparity (welfare, help programs, etc).