Stammering – or stuttering – is a relatively common speech problem in childhood but can also persist into adulthood.

Stammering is characterised by:

• the repetition of sounds or syllables – such as saying ‘mu-mu-mu-mummy’
• prolonging sounds – for example ‘mmmmmmummy’
• pausing or ‘blocking’ – when a word gets stuck or doesn’t come out at all

It usually occurs at the beginning of speech, and people will often avoid certain words or speaking situations to try to hide it.

Stammering varies in severity from person to person. A person might find that they have periods of stammering followed by times when they speak relatively fluently.

Read more about the signs of stammering.

Types of stammering

There are two main types of stammer:

• Developmental stammering is the most common type of stammering that many people are familiar with. It develops during childhood as a child is first learning how to speak.
• Acquired or late-onset stammering can occur in older children and adults as the result of a severe head injury, stroke or a progressive neurological disease (disease affecting the nervous system). It can also be caused by certain drugs or medication, or psychological or emotional trauma.

The rest of this article will focus on developmental stammering.

What causes stammering?

The exact cause of developmental stammering is still unclear, although it is largely thought to be the result of the parts of the brain involved in speech being ‘wired’ differently.

Studies have shown differences in the structure and functioning of the brain of people who stammer compared with most other people.

In young children, the wiring of the brain is still developing, which may be why many children eventually ‘grow out’ of stammering and why it is usually easier to treat children while they are still young.

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

Research has identified several genes that may contribute to stammering that runs in families, although exactly how these genes lead to the condition is currently unknown.

Who is affected

Stammering is common in young children. Estimates for developmental stammering vary, but it is often suggested that around one in 20 children will experience a phase of non-fluent speech.

In around three in every four cases affecting young children, stammering will resolve over time with or without treatment. However, it is difficult to predict when this will happen and some children will require treatment to prevent the problem persisting into adulthood.

The condition is more likely to persist in males than females, which is why there are around four times as many men as women with a stammer. The reason for this is unclear.

It is estimated that one in every 100 adults has a stammer.

Getting help

If you have any concerns about your child’s speech and language development, seek advice.

Treatment is often highly successful in resolving stammers in pre-school age children, especially if it is received as soon as possible, so early referral to a specialist is key.

A good person to contact first may be your GP, who can discuss your concerns with you and refer you to a speech and language therapist (SLT) for an assessment if necessary. Alternatively, many speech and language services accept self-referrals from patients and parents.

You can contact the British Stammering Association helpline on 0845 603 2001 for advice about seeking help and information about the services available in your area.

It may also be worth seeking advice from your GP or an SLT if you are an adult with a stammer and it is having a significant impact on your social and work life.

How stammering is treated

There are many different speech and language therapy approaches that can help people to improve fluency and communication skills in people who stammer.

A therapist will work with you to come up with a suitable plan tailored to your or your child’s individual circumstances.

This may involve:

• working to create an environment in which a child feels more relaxed and confident about their use of language
• working on feelings associated with stammering, such as fear and anxiety
• strategies to improve fluency and communication skills

Electronic ‘anti-stammering’ devices are also available and can be helpful for some people. These are designed to help people control their speech by giving them sound feedback, although they are not generally available on the NHS.

Read more about treating stammering.

Stammering in young children usually involves some obvious outward signs, as well as some less obvious signs.

Problems will usually become apparent while your child is still learning to speak, with most stammers developing between two and five years of age.

You may only notice a problem developing gradually, although in some cases stammering can start suddenly.

Typical signs

Outward signs of a stammer can include:

• repeating certain sounds, syllables or words when speaking, such as saying ‘a-a-a-a-apple’ instead of ‘apple’
• prolonging certain sounds (not being able to move on to the next sound), for example saying ‘mmmmmmmilk’
• lengthy pauses between certain sounds and words, which can make it seem as though a child is struggling to get the right word, phrase or sentence out
• using a lot of ‘filler’ words during speech, such as ‘um’, ‘ah’ and ‘you know’
• avoiding making eye contact with other people

Stammering can be worse in situations where the child is conscious of their speech and may be trying harder not to stammer. These situations might include:

• talking to a person in authority, such as a teacher
• giving a presentation at school or college in assembly or in class
• reading aloud
• speaking on the telephone
• saying their name in registration at school

Associated behaviours

A child with a stammer can also develop some associated physical behaviours that can include involuntary physical movements such as eye blinking, quivering lips, grimacing, tapping the fingers or stamping the feet.

Less obvious signs of stammering can include:

• deliberately avoiding saying certain sounds or words thought to provoke a stammer
• adopting strategies to hide a stammer, such as a person claiming to have forgotten what they were trying to say when they have trouble getting words out smoothly
• avoiding social situations because of a fear of stammering, such as not asking for items in shops or not going to birthday parties
• changing the style of speech to prevent stammering, for example talking very slowly or in an unusual tone of voice
• feeling negative emotions such as fear, frustration, shame or embarrassment because of the stammer

Some children who stammer may also be teased or bullied by other children because of their speech difficulties.

When to seek advice

It is common for young children to have some temporary difficulty with their speech. This does not necessarily mean they have a stammer. However, it is always best to seek advice early on in case it isn’t just a period of non-fluent (‘bumpy’) speech.

A good person to contact first may be your GP, who can discuss your concerns with you and refer you to a specialist speech and language therapist (SLT) if necessary. Alternatively, many speech and language services accept self-referrals from patients and parents.

You can contact the British Stammering Association helpline on 0845 603 2001 for advice about seeking help and information about the services available in your area.

It may also be worth seeking advice if you are an adult with a stammer and it is having a significant impact on your social and work life.

There are many different treatments available for stammering, depending on a person’s age and their individual circumstances.

A speech and language therapist (SLT) will work with you, your child, and educational staff to come up with a suitable treatment plan for your child.

An SLT can also work with adults who stammer to help find ways to improve the fluency of their speech, and psychological therapy may be available to help with any emotional difficulties occurring as a result of speech difficulties.

Speech and language therapy is often available on the NHS for people who stammer, although you may have to wait a few months to be seen because most departments have waiting lists and some treatments (such as feedback devices – see below) may not necessarily be funded.

SLTs with experience in assessing and treating stammering are also available privately, although private treatment can be expensive.

Some of the most commonly used treatments for stammering are described below.

Indirect therapy

In pre-school children, indirect therapy is the method commonly used.

This is often based on the ‘demands and capacities model’, which is based on the concept that children start to stammer when the demands on their speech are greater than what they are able to produce.

These ‘demands’ are often made by the child, as they put pressure on themselves to communicate in a way they can’t yet manage. 

The goal of indirect therapy is to create an environment in which a child feels more relaxed and confident about their use of language. This involves:

• speaking slowly and calmly to the child
• developing a positive parent-child interaction
• avoiding criticising or drawing attention to the child’s stammer
• making the family environment as relaxing and calm as possible

Direct therapy

With school-age children, an SLT may be more likely to choose direct therapy, which may include:

• helping to improve fluency
• helping the person understand more about stammering
• sharing experiences with others who stammer
• working on feelings associated with stammering, such as fear and anxiety
• improving communication skills
• developing self-confidence and positive attitudes

Although stammering that persists beyond the age of six or has been apparent for more than three years is significantly more challenging to treat, direct therapy may also be helpful for some adults who stammer.

A widely used type of direct behavioural therapy in the treatment of young children is the Lidcombe Programme.

The Lidcombe Programme is designed to be carried out by the parents of the child under guidance from an SLT and is based on the principle of providing consistent feedback to the child about their speech in a friendly, non-judgemental and supportive way.

Other therapy options

In addition to direct and indirect therapy, there are some other options that can help people who stammer, particularly adults with a persistent stammer and those who develop a stammer later in life (acquired or late-onset stammer).

These include psychological therapy and feedback devices.

Psychological therapy

Psychological therapies include solution-focused brief therapy (SFBT), personal construct therapy, neuro-linguistic programming (NLP) and cognitive behavioural therapy (CBT).

These therapies do not treat stammering directly, but may be useful if feelings such as stress and anxiety make stammering worse, or if you experience these feelings as a result of your stammer. 

The British Stammering Association has more information on all of the above alternative therapy options.

Feedback devices

Feedback devices alter the way the voice is heard. They include:

• delayed auditory feedback (DAF) – these play your voice back to you a fraction of a second after speaking
• frequency-shifted auditory feedback (FSAF) – these play your voice back to you at a lower or higher frequency
• combined DAF/FSAF devices – these use a combination of both methods mentioned above

These devices are often fitted inside or around the ear, similar to a hearing aid, and they can help improve the fluency of some people’s speech. There are also some applications (‘apps’) for smartphones and computers that work in a similar way.

However, these techniques do not work for everyone and the devices are generally not available on the NHS. However, the British Stammering Association, the main support organisation in the UK for people with a stammer, can provide a device on loan for two weeks if you are a member of the organisation.

You can read more about feedback devices and apps on the British Stammering Association website.