Stammering – also sometimes referred to as stuttering – is a relatively common speech problem in childhood, which can persist into adulthood.

What is stammering?

Stammering is when:

  • you repeat sounds or syllables – for example, such as saying “mu-mu-mu-mummy”
  • you make sounds longer – for example, “mmmmmmummy”
  • a word gets stuck or doesn’t come out at all

Stammering varies in severity from person to person, and from situation to situation. Someone might have periods of stammering followed by times when they speak relatively fluently.

Read more about how stammering can affect you.

Types of stammering

There are two main types of stammering. They’re known as:

  • developmental stammering – the most common type of stammering; it occurs in early childhood when speech and language skills are developing rapidly 
  • acquired or late-onset stammering – is relatively rare and occurs in older children and adults as a result of a head injury, stroke or a progressive neurological condition; it can also be caused by certain drugs or medication, or psychological or emotional trauma

This topic focuses on developmental stammering.

What causes stammering?

It isn’t possible to say for sure why a particular child starts stammering, but it isn’t caused by anything the parents have done.

Developmental and inherited factors may play a part, along with small differences in how efficiently the speech areas of the brain are working.

Speech development

Speech development is a complex process that involves communication between different areas of the brain, and between the brain and the muscles responsible for breathing and speaking.

When every part of this system works well, the right words are spoken in the right order, with correct rhythm, pauses and emphasis.

A child learning to construct simple sentences needs practise to develop the different speech areas in the brain and lay down the neural pathways (“wiring”) needed for the different parts to work well together.

Talking problems can occur if some parts of this developing system aren’t quite co-ordinated. This can cause repetitions and stoppages, particularly when the child has lots to say, is excited, or feeling under pressure.

As the brain continues to develop, some of these problems resolve or the brain is able to compensate, which is why many children “grow out” of stammering.

Sex differences and genes

Stammering is more common in boys than girls. Differences in brain development between the sexes might make boys more vulnerable to speech and language difficulties.

Genes are also thought to play a role. Around two in every three people who stammer have a family history of stammering, which suggests the genes a child inherits from their parents might make them more likely to develop a stammer.

When to get help

You should get advice if you have any concerns about your child’s speech or language development.

Treatment for stammering is often successful in pre-school age children, so it’s important to get referred to a specialist as soon as possible.

Contact your GP or health visitor to discuss your concerns with them. If necessary, they may refer your child to a speech and language therapist (SLT) for an assessment.

In many areas, you can phone the children’s speech and language services directly and refer your child yourself.

The British Stammering Association (BSA) website has information and advice for parents, and a helpline you can call on 020 8880 6590 to find out about the services available in your area.

If you’re an adult who stammers and it’s having a significant impact on your social and work life, you may want to ask your GP to refer you to an SLT.

Treatments for stammering

There are different speech and language therapy approaches that can help people who stammer speak more easily.

You’ll work together with a therapist to come up with a suitable plan tailored to you or your child.

This may involve:

  • creating an environment where your child feels more relaxed and confident about talking
  • strategies to increase fluency and develop communication skills
  • working on feelings associated with stammering, such as fear and anxiety

Electronic devices to reduce stammering are also available and can help some older children and adults, but they’re not usually available on the NHS.

Read more about treating stammering.

Who’s affected

Studies suggest around 1 in 20 young children go through a phase of stammering.

Around four in five children who stammer will grow out of it, although it’s difficult to predict when this will happen in a particular child.

It’s estimated stammering affects around 1 in 100 adults, with men being around four times more likely to stammer than women.