Researchers have discovered a way to block male mice from fatherhood—with minimal side effects. The technique, which could help lead to a male birth control pill, doesn't mess with hormones or with sperm itself, AFP reports. Instead, it affects sperm's ability to travel through the male body. By genetically altering mice, researchers "turned off" two proteins that are needed to move sperm through the reproductive system.
That made them infertile "without affecting the long-term viability of sperm or the sexual or general health of males," says a scientist involved. "The sperm is effectively there, but the muscle is just not receiving the chemical message to move it." A chemical, rather than genetic, version of the technique could factor into the creation of a male birth control pill, though it could be 10 years before we see it, he adds. "If you're a young guy and you get to the stage where you wanted to start fathering children, you stop taking it and everything should be OK," the researcher tells ABC via AFP.