In 1839, Charles Goodyear came up with a simple rubber invention that changed everything. Not the tire – that had already been around for years before. No, this small rubber flap was the world’s first condom: a simple, snug-fitting device that has probably done more to shape the world’s population than anything else.
The condom was but the first step in a long history of contraceptives and other tactics designed to protect women from unwanted pregnancies. As far back as Ancient Rome, lovers of all stripes would sometimes don dried pig bladders to prevent the spread of sexually transmitted infections. It’s hard to imagine the course history might have taken in a world without contraceptive options: as our population spirals upwards past the eight billion mark, it’s easy to forget that we could be living in a world with far, far more.


As Earth’s population piles up, what does the future hold for couples who want to play safe? Birth control products are among the most difficult products to engineer and test. Not only are they designed for healthy adults who may force them to operate in a variety of (kinky) scenarios, but they must work 100 per cent of the time, at all times – otherwise any would-be consumers will find themselves in a disastrous scenario. Unplanned pregnancies can greatly impact lives, affecting job performance, leaves of absences, and, in some cases, the moral crisis of a potential abortion.

One avenue scientists are looking into involves literally “freezing” eggs in the body. Women are born with all their eggs in place and ready to grow: each proto-egg is nestled in a follicle. Baby boys, on the other hand, develop Müllerian-inhibiting substance: a chemical that prevents them from growing those same proto-eggs in favor of… well, you know. In mice, inserting MIS into an adult mouse essentially hits “pause” on menstruation and further egg development: tricking the body into thinking it’s turning male, thereby inhibiting the development of further eggs.
Already, scientists are testing this process with cats, dogs, and other domestic mammals as part of attempts to curb unwanted litters; a more humane replacement to the old practice of spaying or neutering pets. In the future, it may keep Earth’s population manageable.