When I was 7 or 8, my next-door neighbor (who was 12 at the time, I believe) told me that when a woman loses her virginity, a bone breaks in her clit and it's extremely painful. For a while, I wondered why anyone would want to have sex if it was that painful!
A childhood belief about rude bits

others believed things like this
- I used to beleive that a catacism(spelling?) was an extremely painful Christian version of a bris.— Mike
- I used to believe that Marilyn Manson was a extremely scary woman!— Tim_NOrway
- i used to believe that a sign in a cafe bone-fide meal meant meat with a bone in it— roy
- That if a pig loses its voice, it's disgruntled.Anon
- that actors went to the toilet during the ad breaks.— ash
- I used to think that if a mirror with me in it breaks, I break.Anon