Congenital hearing loss: newborn screening, causes and support

Congenital hearing loss is reduced hearing present from birth. NDCS explains that childhood deafness can be permanent, temporary, progressive (increasing over time) or fluctuating (changing over time). It may affect one ear or both, and it can range from mild to profound.

NHS inform describes 2 main types of hearing loss in general: sensorineural, from damage to the inner ear or hearing nerve, and conductive, where sound cannot pass from the outer ear to the inner ear. Some people are born with hearing loss, as NHS inform notes, although most cases develop as you get older.

For babies, the key point is timing. The brain learns language by hearing it, so recognising hearing loss in the first weeks and months allows support to start at the point where it is most useful.

The NHS says newborn hearing screening is a test to find babies who have hearing loss. It takes a few minutes and you get the result immediately. It is usually offered in hospital or at home before your baby is 4 weeks old, though it can be done up to 3 months of age, and sometimes you may be invited to a clinic.

A small soft earpiece is placed in the baby's ear and gentle clicking sounds are played to check how the baby responds. The NHS says the test is done when your baby is settled or asleep, it is not uncomfortable and it has no known risks. If it does not give a clear result it will be repeated or your baby will be offered a second, different test.

If you are not offered a screening test, the NHS says to ask your health visitor or GP to arrange an appointment, or contact your local hearing screening service.

The NHS explains that an unclear result in one or both ears does not mean a baby has hearing loss; it means a second test is needed. An appointment will be made with a hearing specialist at an audiology clinic, which should be within 4 weeks of the screening test.

The appointment usually takes about 1 to 2 hours, including time to settle the baby, and parents can stay. The second test involves placing 3 small sensors on the baby's forehead, back of the neck and shoulder, with soft headphones and gentle clicking sounds, to show whether the hearing nerve responds. It can take up to 15 minutes and gives more detailed information, and the specialist can usually give results at the end of the appointment and explain whether more tests are needed.

NDCS explains that congenital deafness is often caused by genetic factors, in which a gene variation affects hearing. Genetic deafness can be syndromic (part of a collection of related symptoms) or non-syndromic, and can be inherited, though most children with genetic deafness do not have any family history of deafness.

Infection during pregnancy is another cause. NDCS says CMV is the second most common cause of congenital deafness in the UK, and that rubella, toxoplasmosis and herpes infections can also cause deafness in unborn babies.

Some babies become deaf shortly after birth, especially premature babies who may develop an infection that causes deafness or be treated with ototoxic medication. NDCS says severe jaundice or a lack of oxygen during birth can also cause deafness.

The NHS says the newborn test does not pick up all types of hearing loss and that children can develop hearing loss later, so checking your child's hearing as they grow is important. The checklist in the personal child health record (the red book) explains how to check.

NHS inform lists signs in babies: a baby who is not startled by loud noises, does not turn towards the source of a sound when under 4 months old, does not say single words by the time they are 1 year old, notices you when they see you but not when you call their name, or hears some sounds but not others.

In children it lists being slow to learn to talk or not being clear when speaking, often asking you to repeat yourself, not replying when called, talking very loudly, turning the television up very loud and watching other people to copy instructions. If you notice any, speak to your health visitor or GP.

After screening, audiology clinics carry out more detailed testing to establish whether hearing loss is present, in which ears and how severe. NDCS describes different types of hearing tests used with children and levels of deafness from mild to profound.

Further tests may be arranged to look for the cause, which can include genetic testing, tests for infections such as CMV, imaging and checks on the ears. NDCS offers a resource to help families understand the different medical tests that can be used to help identify the cause of deafness.

If hearing loss is found, the audiology team and the child's doctors plan support with the family, which may include ENT assessment where needed. NDCS provides information and support for families with children and young people with hearing loss.

NHS inform describes options that may help to improve ability to hear and communicate: digital hearing aids available through the NHS, bone anchored implants for people who cannot use hearing aids, middle ear implants, cochlear implants for people who find hearing aids are not powerful enough, and lip reading or sign language such as British Sign Language.

The NHS notes that if hearing loss is permanent a specialist will often recommend hearing aids, which make sounds louder and clearer but do not make hearing perfect, and that some people need a hearing implant. For temporary conductive loss, such as glue ear, the NHS says treatment may be watchful waiting, temporary hearing aids or grommets.

NDCS offers support and information to families with children and young people with hearing loss, including a helpline, as the NHS notes.

The NHS says hearing loss can affect a child's speech development and progress at school, which is why support from the earliest stage matters. Families may combine hearing technology with sign language or other communication approaches, depending on the child.

NDCS describes information about deaf identity and culture, support for children with additional needs and communication. Joining family support groups and speaking to a teacher of the deaf can help parents decide what works for their child.

Newborn hearing screening and follow-up audiology are part of the NHS programme, and hearing aids for children are provided through NHS audiology services.

Private audiologists can test hearing and fit hearing aids, but it is important that any concern about a baby or child's hearing is also shared with the GP, health visitor or NHS audiology service so that screening, follow-up and educational support are coordinated.