Zapping away fatherhood

'Sonicated' Sperm: Scientists Test Ultrasound as the Next Male Contraceptive | Healthland | TIME.com

Have I posted a story about this before?* I can't quite remember, but anyway, from the report above:

In the study, the rats’ testes were exposed to high frequency ultrasound at 3 MHz for 15 minutes each, two days apart. The sessions were enough to kill the existing sperm in the testes and stop the development of additional sperm. The first study to look at the effect of ultrasound on sperm production, in the 1970s, showed that the depletion was temporary, and Tsuruta hopes his studies will show the same result...

Some men are keen to get in on the technique:

Tsuruta stresses that the procedure isn’t something you should try at home, despite the fact that commercial ultrasound machines are available online and men are apparently purchasing them for this purpose. “I get emails asking me what conditions men should use,” Tsuruta says. “This is really not something you should do at home because we don’t know nearly enough about its safety and reversibility and what other effects there might be long term.”

I'm not sure that something that is working to disable sperm cells could be trusted to not be causing damage to testicular cells you don't want damaged.

* Yes I did - in 2010. It was a story about the same researcher in fact, and I am not entirely sure why this has made it to the news again last month.