Ernst Grafenberg

German doctor and scientist Ernst Grafenberg was born on Sept. 26, 1881. (If he was still with us, he’d be 133 years old.) His contributions to sexual research include creating the first intrauterine device (IUD) in 1929, then known as the Grafenberg ring, and research into how women’s urethras play into orgasm.

But his name is more famously associated with the G-spot, G as in Grafenberg. The G-spot was given his name in 1981.