[Jjames653 (OP)]

I've been looking for a male birth control and I've found that exposing the testies to heat for a certain period of time decreases the sperms count and motility the point of infertility. However I still have some doubts. The biggest one being that the heat supposedly disrupts the spermogenisis of the cells. Which can cause changes into the dna structure that could lead to birth defects. What I'm wondering is if in two to three years I decide I want to have children. I stop treatment. Allow 6 months for the sperm count to get back to normal. Would the dna struck of the sperm go back to what it was before or if the sperm had acquired any abnormalities in there dna would those abnormalities continue to be reproduced?

[evan_au]

This overheating of the testes does occur naturally in the ≈1% of males that have undescended testes.
These are held at body temperature (37C), instead of a couple of degrees cooler in their normal location outside the body.
It results in reduced fertility (not infertility).

It carries with it an increased long-term risk of testicular cancer (amongst other things - like malformation visible under the microscope after 2 to 4 years).
See: http://en.wikipedia.org/wiki/Cryptorchidism#Later_cancer_risk

Condom use is reversible, has a much higher success rate and much lower medical risk than cooking your testes.