To explain to her poor husband why she's feeling insane during certain time of the month, Wendy Bryan of I Heart Guts (who makes gems like the Testicle Plush and other internal organ plushies) created this fantastic The Good Ol' Menstrual Cycle poster.
Guys, from experience I can tell you that the majority of the time you'll get a chuckle out of your wives and girlfriends. At certain time, however, you'll be lucky to get out alive. So, what are you waiting for? Get yours today from the NeatoShop: Link