New Birth Control Method For Men Might Be Close

Scientists at Michigan State University may be close to contraceptive methods that are an alternative to getting snipped or having to wear condoms, according to a study published this week. But there is at least one side effect that could make men squeamish: smaller testicles.

The findings of Michigan State animal biologist Chen Chen and his team were published Tuesday in the science journal Nature. The research team successfully turned off the gene that controlled sperm production in mice.

According to the report, human genes for reproduction are similar to mice, and the finding provides a lead for future research for contraceptive uses for men.

Watch: New Birth Control Method For Men Might Be Close

“More than 500,000 men get vasectomies every year,” said Chen in a university publication. “There’s a huge market for this research, and now we further understand the genetic underpinnings of sperm development in mammals.”

Chen's team was able to isolate and block the gene that controls sperm production in mice, which then were bred without that specific gene. The mice offspring produced fewer sperm and were effectively sterile. They also had smaller testicles.

The mice bred without the gene had few, if any, side effects and no obvious differences in growth, behavior or appearance, other than having small testicles.

Chen compared the process to fixing a water leak.

"Rather than stuff a rag into the leak and hope that it works, we went to the source and turned off the water supply,” Chen said.

The research of Chen and his was funded in part by the National Institutes of Health and the Michigan State AgBioResearch.

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