Young children often go through a short period of stuttering, but this phase is very transient. For a small percentage (less than 1%), the stuttering progresses from simple repetition of consonants to repetition of words and phrases. Later vocal spasms develop with a forced, almost explosive sound to the speech.

Stuttering tends to run in families, but it is unclear to what extent genetic factors are important. There is also evidence that stuttering may be associated with some neurological deficits, but psychological components tend to make the symptoms worse or better within each case. Surprisingly, people with significant speech difficulty often don't stutter when singing or when they are alone talking to themselves. Stuttering tends to persist into adulthood more in males than females.

• stuttering
• hesitancy in starting sentences or phrases

There is no one best treatment known for stuttering. Most early cases are short term and resolve on their own. In persistent cases, speech therapy may help. Research on therapies is on-going and should be investigated to determine what kinds of help to seek and which kinds may be less useful.

Some people who stutter find that when they read aloud or sing they do not stutter. It can be helpful for the child's self esteem to practice reading aloud or singing.

In the majority of children who develop stuttering, the phase is only transient and their speech returns to normal. Obvious increases in speech difficulty may lead to persistence of stuttering into adulthood.

• social problems may occasionally develop (the child may be so afraid of stuttering that he or she does not speak)