Scientists from the University of North Carolina have been investigating ultrasonic radiation as a form of contraception.
Basically, the idea is that a concentrated high-frequency audio wave, aimed at the testicles, can result in infertility in men for up to 6 months.
The ultrasound equipment they have been using is the same type usually used for physical therapy, and they have seen some success in using the technique on rats. A team of researchers led by UNC’s James Tsuruta has shown that that exposing the testes of rats to two 15-minute doses of ultrasonic radiation could reduce sperm counts in the rats to levels that, in humans, would result in infertility.
Preliminary studies were performed in the 1970′s, but didn’t ever see the light of day. Although having high-frequency waves aimed squarely at your testicles sounds somewhat…intimidating, the method shows promise, as it seems to be safe, potentially reversible, non-painful, and very cheap.
Long terms studies still need to be completed to find out if there are any lingering effects to sperm after the effect wears off, but so far the project looks promising. You can see the provisional version of the researchers’ findings published in Reproductive Biology and Endocrinology.