Researchers Develop New Type of Male Contraceptive

Researchers at the University of North Carolina, School of Medicine have found that exposing testicles to a burst of ultrasound causes a reduction in the number and amount of sperm produced. The team, as they write in their paper published in Reproductive Biology and Endocrinology, has found that repeated exposure to small doses of ultrasound can inhibit sperm production in monkeys for up to six weeks.

The team, as reported in Popular Science, first tested the procedure on rats and found that rolling an ultrasound transducer similar to that used to take images of babies still in the womb, over the testicles resulted in a dramatic reduction in sperm count. They then tried various scenarios and discovered that two fifteen minute treatments two days apart reduced sperm counts to a level that would be consistent with infertility.

Encouraged by their results, the unnamed foundation paying for the study ponied up for a second run at the University of California. This time the researchers found if they applied an ultrasound transducer to the testicles of the monkeys in three thirty minute sessions two days apart they could cause the monkeys to be sterilized for up to six weeks. It's not known what might happen if the monkeys were to receive another dose before that time, but the researchers reported the monkeys, after at first being hesitant, began to enjoy their little sessions.

Researchers from both studies report that the procedure is painless and actually, other than the feeling of the transducer against the body, cause no internal sensation at all for the recipient, though of course, it's impossible to say for sure until a human subject is used.

This is not to say that doctors will start offering the procedure to human males that are willing, however, as extensive testing will need to be conducted to see if any lasting damage occurs or if other side effects might be encountered from the application of the ultrasound after repeated exposure. And then, even that might not be enough as long term testing might have to be done to ensure that it doesn't cause or increase the chances of developing testicular cancer.

The reason the procedure would have to go such extensive testing, despite the fact that ultrasound is already in use regularly for pediatric visits is because of the increased number of times that it would need to be used to be considered a completely effective form of birth control.