I don't know about lowering crime rates, but I do think the 45 million abortions are a contributing factor to why our government keeps the floodgates open at the border. They want to replace the 45 million Social Security payers.
Having had a while to think about it, I really do believe an argument could easily be made drawing a correlation between RISING crime and abortion, at least in a specific way. Most women who have abortions suffer psychologically afterward, and very, very few of those women seek any form of counselling. I am only speaking from my own experiences here, and from what I know of other women whom have had abortions. A very common way to "numb the pain" of the aftermath of abortion is to turn to drugs and alcohol. When not taken for strictly recreational use, drugs and alcohol can quickly send one's life into a downward spiral: Addiction to illegal drugs and alcohol can (and often does) lead to theft of any kind--one can't get a fix if one lacks the funds; said addictions also have a negative effect on one's judgement, which can land an already traumatized woman into any number of horrific situations.
You know what stats I would love to see, that the CDC et al will never be interested in tracking? I would love to know what becomes of a post-abortive woman's life in the two years or so following her abortion. Are these women more likely to commit crimes? Are they more likely to become victims of crime? All I can do is rely on my own experiences, as I said, and the experiences of other women like me--and we can answer both of those questions with an unequivocal yes.