Fast Facts

• The prevalence of speech sound disorder in young children is 8 to 9 percent.

• By the first grade, roughly 5 percent of children have noticeable speech disorders; the majority of these speech disorders have no known cause.

• Usually by 6 months of age an infant babbles or produces repetitive syllables such as “ba, ba, ba” or “da, da, da.” Babbling soon turns into a type of nonsense speech called jargon that often has the tone and cadence of human speech but does not contain real words.

• By the end of their first year, most children have mastered the ability to say a few simple words.

• By 18 months of age most children can say 8 to 10 words and, by age 2, are putting words together in crude sentences such as “more milk.”

• At ages 3, 4, and 5 a child’s vocabulary rapidly increases, and he or she begins to master the rules of language.

• It is estimated that more than 3 million Americans stutter. Stuttering affects individuals of all ages but occurs most frequently in young children between the ages of 2 and 6 who are developing language. Boys are 3 times more likely to stutter than girls. Most children, however, outgrow their stuttering, and it is estimated that fewer than 1 percent of adults stutter.

• Between 6 and 8 million people in the United States have some form of language impairment.

• More than 12,000 babies are born each year with a significant hearing loss, which can affect speech and language development.

Source: Compiled from fact sheets produced by the National Institute on Deafness and Other Communication Disorders (NIDCD).