what I read was about what is called "pediatric spaying" (2 months). Basically they were saying, adoption agencies were letting the kittens go at two months with a certificate for a free spay at 4 months, but a certain number would either run off or not be brought in for the procedure, thus increasing the number of unwanted kittens again.
By doing it at 2 months, the kittens were spayed BEFORE going to their forever homes and the agency did not have to worry about them making more kittens.
This is the reason for doing it early.
I found this great FB page
http://www.facebook.com/media/set/?s...17234231669766
lists free spay/neuter clinics all over the US. You don't have to sign in to facebook to see it. Lots in Wisconsin but I put up the main page so others could find their state.