An emerging option for male birth control might be even more appealing to potential users than expected. Preliminary research released Sunday suggests that NES/T—a once-daily gel applied to the shoulders—can effectively suppress men’s fertility within a matter of weeks.
Just in case you’d like to know: Alpaca sex is weird, biologically speaking. In a recent paper, scientists have presented evidence that male alpacas impregnate their partners by thrusting their penises all the way up inside the female’s uterus—a tactic not documented with any other mammal species to date.