Stuttering is a speech disorder where the normal flow of speech is broken up by repeating or lengthening sounds, syllables, or words. A person may also have trouble getting a word started. Stuttering is most common between the ages of 2–6, as language skills are developing. Most children outgrow stuttering, usually by age 5.

How common is stuttering?

Approximately 5 percent of people will stutter during some part of their lives. It is most common between the ages of 3–4, when 8–11 percent of children experience stuttering. And it is three to four times more likely in boys than girls. More than 80 percent of children who stutter will recover spontaneously (meaning, with or without treatment). For approximately 1 percent of the global population, stuttering is lifelong.

Stuttering causes and risk factors

Research suggests that stuttering is caused by a variety of factors, including genetics and neurophysiological issues. Despite popular beliefs, emotional problems and parenting style do not cause stuttering. While it’s not possible to determine with certainty which children will stutter, there are some factors that indicate a greater likelihood of stuttering:

  • Sex of child, as boys are at a higher risk than girls for persistence of stuttering
  • Family history of persistent stuttering
  • Stuttering that has been present for more than 6–12 months with little improvement
  • Age of onset – children who start stuttering at age 3½ or older  
  • Co-occurring speech and language impairment

What does stuttering sound like?

The following are some common types of stuttering:

  • Monosyllabic whole-word repetitions (e.g., "Why-why-why did he go there?")
  • Part-word or sound/syllable repetitions (e.g., “L-l-l-l-let’s go.”)
  • Prolongations of sounds (e.g., “I’m ssssssssssorry.”)
  • Audible or silent blocking (filled or unfilled pauses in speech)
  • Words produced with an excess of physical tension or struggle

The frequency and severity of stuttering may fluctuate from day to day and in relation to the speaking situation. Stuttering is often more severe when there is increased pressure to communicate (e.g., competing for talk time, giving a report at school, interviewing for a job).

Secondary, avoidance, or accessory behaviors may also be present:

  • Distracting sounds (e.g., throat clearing, insertion of unintended sound)
  • Facial grimaces (e.g., eye blinking, jaw tightening)
  • Head movements (e.g., head nodding)
  • Movements of the extremities (e.g., leg tapping, fist clenching)
  • Sound or word avoidances (e.g., word substitution, adding unnecessary words)
  • Not answering or asking questions in class or not talking as much due to speaking avoidance
  • Avoidance of social situations
  • Fillers to mask moments of stuttering, such as “uhh,” “umm,” or “you know”

How is stuttering diagnosed? 

speech-language pathologist (SLP) diagnoses stuttering by assessing speech in various contexts (e.g., conversation, oral reading, pretend-play activities). The SLP may film or record the child talking or may check speech patterns in other ways. Your child may also need a physical exam and other tests to rule out health problems that affect speech development, such as hearing problems. Talk with your child's doctor if you have any concerns about his or her speech, if stuttering lasts for more than 6–12 months, or if stuttering runs in your family.

Developmental vs. persistent stuttering

Stuttering that starts during a child's early language-learning years (ages 2–6) and goes away on its own before puberty is called developmental stuttering. It is a normal part of language development. Most children are not bothered by it and may not even notice that they're doing it. This type of stuttering may come and go for a while. Then it may slowly decrease until it doesn't occur anymore.

Stuttering that persists, gets worse, or does not go away over time, is called persistent stuttering. This type of stuttering can be embarrassing and hard to deal with. It typically does not go away entirely, even with treatment. Treatment of persistent stuttering aims to lessen the severity, increase naturalness of speech, and make stuttering less tense and difficult for the speaker.

How can I help my child who is stuttering?

  • Talk to your child in a slow, relaxed way. Pause frequently; avoid interrupting or filling in his/her words or completing sentences. After your child is finished speaking, wait a couple seconds before speaking yourself.
  • When asking questions, try not to ask one directly after another. When trying to gather information about your child’s day, try to start with phrases like “I wonder.” This takes pressure off the child to respond quickly.
  • Reduce the speaking demands of having your child summarize or re-tell lots of recent events or information when visiting with friends and family. Instead, let the child share recent experiences naturally.
  • Take a few minutes each day to spend some relaxed, one-on-one time with your child. Follow your child’s lead, and let your child be the center of attention. No iPad, TV, or screen time during this time.
  • Slow the pace of life in the home, especially conversations. Make sure family members take turns talking and avoid interrupting.
  • Help build your child’s confidence. Be specific and descriptive. Instead of saying “that’s great,” say “I like the way you put away your books, you’re so helpful.”
  • Do not draw attention to his/her stuttering, particularly if your child is not aware of it.
  • Maintain a calm demeanor when your child stutters. Maintain eye contact and use positive facial expressions and body language. He or she is likely to notice if a parent or caregiver looks concerned or upset. Show that you are focused on the message rather than how he or she talks.
  • If your child is getting treatment for stuttering, don’t set perfect speech as the goal. Rather, expect treatment to help your child to arrive at more natural speech, with less struggle and work. Avoid using words like “correct” or “better” speech when talking about treatment and/or speech goals and instead opt for words like “easier” speech.
  • Be aware that children who persist in stuttering are “hard-wired” to be more disfluent and this is not due to lack of effort or success in treatment.
  • Life events or transitions (e.g., moving to new town/school, divorce, starting or ending a school year, friendship stressors) can temporarily trigger and/or exacerbate stuttering.

Additional resources:

Speech Language Pathology specialists at C.S. Mott Children’s Hospital

Childhood Fluency Disorders (American Speech-Language-Hearing Association)

Stuttering (American Speech-Language-Hearing Association)

Resources for parents on stuttering (The Stuttering Foundation)


Written by Erin Papcun, MA, CCC-SLP, Lindsay Reilly, MA, CCC-SLP, and Laura Scott, MA, CCC-SLP.
Reviewed by Sara Laule, MD

Updated May 2018