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Medically reviewed by Last updated on Jul 4, 2023.

What is Stuttering?

Harvard Health Publishing

Stuttering is an interruption of the normal flow of speech, which takes on many different patterns. Commonly, it involves either saying a string of repeated sounds or making abnormal pauses during speech.  

In early childhood, stuttering is sometimes part of normal speech development. In fact, about 5% of all young children go through a brief period of stuttering when they are learning to talk. Stuttering typically is first noticed between the ages of 2 and 5. It usually goes away on its own within a matter of months. In a small number of children (around 1%), stuttering continues and may get worse. Boys are more likely to stutter than girls. 

Researchers still are trying to determine why stuttering occurs. It runs in families, and genetic (inherited) factors probably play a larger part than previously recognized.  

Some studies suggest the problem may be due to subtle changes in the brain pathways that process speech and language. Emotional factors may make the stuttering more pronounced but are not the cause.  

After age 10, it is unusual for someone to begin stuttering if he or she has never stuttered before. In rare cases, stuttering can develop after a stroke or brain injury, or rarely as a side effect of some drugs, especially those used to treat seizures or severe psychiatric illness. 


Some characteristics of stuttering speech include:  

It is important to note that most children repeat sounds or syllables and pronounce words incorrectly when they are learning to speak. This is referred to as normal dysfluency.  

However, with true stuttering, these speech behaviors occur more often and repetitions of sounds or words last longer than half a second. In addition, normal problems with fluency tend to come and go, or happen only at certain times (such as when a child is tired or excited), but true stuttering is present most of the time.  

Once a child begins to stutter, he or she may feel embarrassed, self-conscious or anxious when asked to speak. The child may find it hard to socialize with friends and also may intentionally avoid situations where talking is expected, such as telephone calls, classroom discussions and school plays. 

Somewhat unexpectedly, many children who stutter have no problem when they sing. According to some experts, this is because speaking and singing often come from opposite sides of the brain, especially in right-handed people.  


Although episodes of stuttering speech are usually easy to recognize, a diagnosis of true stuttering should always be made by a professional. 

If you are concerned that your child seems to be stuttering, talk with your child's doctor. Occasionally, the doctor may refer you to a speech-language pathologist for further evaluation.  

As part of your child's evaluation, the speech-language pathologist usually will ask questions about your child's history, including development, behavior and school performance. Then he or she will speak with your child to evaluate speech and language skills. Part of this interview may be recorded. A full evaluation can take several hours. 

Expected Duration

Many cases of stuttering last for only a few months and most children who stutter will stop completely before the end of their childhood. Only about 1% of children develop persistent stuttering that lasts into adulthood. 


Because doctors do not know why children stutter, there is no way to prevent this speech disorder. However, early treatment of stuttering may prevent worsening of symptoms and long-term problems. 

Currently, researchers at the U.S. National Institutes of Health and elsewhere are conducting genetic studies to find out whether some people inherit a risk of stuttering. If these studies identify a gene for stuttering, it may be possible to identify and treat high-risk children early in life. 


If your child stutters, you can help by doing the following:  

f your doctor refers you to a speech-language pathologist, discuss your expectations before treatment begins. Speech-language pathologists use many different types of speech therapy to treat stuttering, and the success of each type of therapy varies from person to person. Some of the most popular methods include: 

In rare cases, doctors have tried using drugs to treat severe stuttering. But these drugs often have side effects that are worse than the speech disorder itself.  

When To Call A Professional

Call your doctor if your child:  


Most children who stutter eventually improve, even without therapy. Among those with more severe stuttering and those who continue to stutter as adults, speech therapy usually can keep these symptoms to a minimum. 

Additional Info

National Institute on Deafness and Other Communication Disorders

American Speech-Language-Hearing Association (ASHA)

National Stuttering Association

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.