Stuttering Fast Facts Stuttering is a speech fluency disorder characterized by frequent repetitions, pauses and prolongations that interfere with the normal flow of speech. Stuttering may also be referred to as stammering, especially in England, and by a broader term, disfluent speech. It is estimated that more than 3 million Americans stutter. Four times more men than women stutter. While stuttering most frequently occurs in young children as they develop language skills, it can affect individuals of all ages. The precise mechanisms that cause stuttering are not understood (although there is reason to believe that many forms of stuttering are genetically determined). Many people who stutter can speak fluently some of the time, such as when they speak and sing in unison with another person (the "choral effect"). Stuttering is typically diagnosed and treated by a Speech Language Pathologist (SLP). People who stutter are self-conscious about their condition and often let it affect the choices they make in terms of their job and social interaction. People who stutter typically have IQs 10 to 14 points higher than the general population. Famous people who stutter include Winston Churchill, Marilyn Monroe, James Earl Jones, Sir Isaac Newton, King George VI of England, Bruce Willis, Jimmy Stewart, Carly Simon, John Stossel and Bill Walton. << BACK TO NEWSLETTER