(CHAPEL HILL, N.C.) -- A couple zaps to the testicles might be the future of contraception, according to a new animal study published in the journal Reproductive Biology and Endocrinology.
Researchers from the University of North Carolina at Chapel Hill found that zapping the testicles of rats with a therapeutic ultrasound machine -- the type normally used by physical therapists to treat muscle injuries -- abolished the germ cells that produce sperm. The best results were seen when the testes underwent two 15-minute zap sessions.
"This caused rat sperm counts to fall far below the (equivalent) range seen in normal fertile men, and this happened in just two weeks," said James Tsuruta, lead author of the study and assistant professor of pediatrics in the laboratories of reproductive biology at UNC Chapel Hill.
"This method dropped sperm counts 10-times lower than just using heat," said Tsuruta. "It's going to be exciting to figure out how this exactly works: if it's safe to use repeatedly, how long it lasts, and if it's reversible."
Of course, more research is needed to see whether the treatment could someday be available to men, but researchers said the zaps show promise as a cheap, reliable and reversible birth control option in the future.
Dr. Paul Turek, director of the Turek Clinic in San Francisco said the research is a "nice feasibility or proof of concept study, [but], as with other studies in medicine, it is always wise to remember that mice are not men."
Copyright 2012 ABC News Radio