What's really going down when a woman gets off? WIRED's new video, "The Female Orgasm, Explained With Science Projects," tackles this question against a backdrop of clay models and chemical reactions. (We're guessing your middle school never thought to combine science class and sex ed.) First lesson: With its 8,000 nerve endings, the clitoris is the clear star of the female orgasm; it's "no wonder up to 70% of women require direct clitoral stimulation to achieve orgasm," the video notes. What's more surprising is the video's anal sex revelation. Apparently, 94% of women who had anal sex reported they could climax while doing so, putting an end to the myth that women in different-sex partnerships engage in anal sex merely to please men. (Of course, most of these orgasms were probably not through anal stimulation alone.) A lucky 10% of women are able to orgasm through exercise — talk about gym motivation. A scant but still surprising .3% of childbirths, meanwhile, actually induce orgasm. That effect is especially useful considering that a woman's pain threshold increases by 107% during orgasm. See below for WIRED's full set of findings on the oft-misunderstood female orgasm.