A new human sex hormone has been found, a new study says. The naturally occurring substance could lead to the long-sought male birth control pill, researchers cautiously speculate.



Gonadotropin-inhibitory hormone (GnIH)—first identified in birds about a decade ago—was recently discovered in the hypothalamus of the human brain. The hypothalamus produces hormones that regulate sleep, sex drive, body temperature, and more.



GnIH suppresses another hormone—gonadotropin-releasing hormone (GnRH)—which spurs the release of additional hormones, which prime the body for sex and reproduction. So scientists cautiously suggest that contraceptives based on the newfound hormone could someday be possible. 



"That is an idea we've toyed with," said study co-author George Bentley, a biologist at the University of California, Berkeley. But "we don't know enough