Can Exposure to Loud Noise Cause Hearing Loss in Babies?
Are you worried about being exposed to loud noises during pregnancy? Exposure to loud music and other sounds can increase stress levels and raise the risk of hearing loss in unborn babies. So before you plan a concert visit or a night out with friends, find out what booming basses could do to your child.
Noise-induced hearing loss can be caused by many sources, including aeroplane engines, rock concerts, noisy workplaces or a car radio played at a high volume. To prevent hearing loss in your unborn baby, you should avoid such loud noise. But there is no need to keep to a completely silent environment, as soft sounds can be beneficial to an unborn child.
What Can Babies Hear In The Womb?
Between 0 and 16 weeks
At this very early stage, the unborn baby is surrounded by sound, vibrations and motions which can be ‘felt.’ Audiology studies have found that voices and music can be heard in the womb, mainly as patterns of rhythm, stress and pitch.
At around 16 weeks, babies will start to react to sound even though the baby’s ear is not fully complete until 24 weeks. At 16 weeks the unborn baby is particularly receptive to its mother’s voice. This is because the vibrations that travel through her body to the womb are stronger than noises coming from outside the womb.
At 20 to 24 weeks, the unborn baby can recognise the deeper tones of its father’s voice.
Around 24 weeks
The unborn baby’s outer, middle and inner ear are well-developed by 24 weeks gestation. The cochlea has fully formed, so the baby’s ear can effectively transmit sounds to the brain for processing.
From 24 weeks
Parents of the unborn child can stimulate their baby and develop early communication skills by playing music and reading right from the start. Babies respond well to music as the melody, words and pitch help the baby to remember. This development of listening before birth is important to the progression of listening and attention skills after birth
Babies Hear Sounds Muffled
Can an unborn baby hear loud noises? For unborn babies, loud noises will sound muffled in the womb. A mother’s body will dampen loud noise and lower the volume before it reaches the developing baby’s ears. The is amniotic fluid filling the middle ear, prevents the eardrum from amplifying sounds as it will once the baby is born.
The Effects Of Loud Noises On Unborn Babies
- 90 to 100 decibels
Continuous exposure to loud noise over about 90 to 100 decibels – about the level of a chainsaw, can raise the unborn baby’s risk of hearing loss. Studies have shown that loud noises can also increase the chances of premature birth and low-birth-weight.
- 150 to 155 decibels
Shorter occasional exposure to loud noise in the 150 to 155-decibel range, the level next to a jet engine, can lead to hearing loss and developmental problems. A sudden loud noise also can startle an unborn baby, causing increased activity shortly after the fetus hears the sound.
What are the risks?
- Increased chances of premature birth
- Low-birth weight
- Congenital hearing loss
- Developmental problems
Soft Music Soothes Mum And Baby
While excessively loud noise can potentially cause hearing loss in babies, softer sounds might provide some benefit. Listening to pleasant music played at a level of 70 decibels or lower can soothe both mother and baby.
You should avoid discordant music and loud noises since audiologists have done animal studies that have indicated changes in brain structure when fetuses are exposed to this kind of music.
Mother’s Voice is Clearest
When pregnant, the clearest noise a baby will be able to make out is the mother’s voice. While most sound passes through the air, and then through the uterus, when a mother speaks, the sound of her voice reverberates through her bones and body, amplifying it.
Studies have shown that an unborn baby’s heart rate increases when the mother’s voice is heard, suggesting the baby becomes more alert. So a mother who reads out loud carries on conversations and sings songs to her unborn baby, will help the baby to get to know her voice.
Dads, Don’t Despair!
Babies also learn to recognise other voices and sounds that they hear often in utero. Researchers have found that newborns react differently to words and sounds that were repeated daily throughout the third trimester compared to those they never heard during pregnancy.
Additionally, inside the uterus, it turns out that deeper, lower sounds are easier to make out than high-pitched ones.
Support Your Baby’s Hearing In Utero
So what can you do to make sure your baby’s hearing develops normally? Should you play music through headphones pressed against your belly? Should you avoid loud noise and rock concerts?
It is recommended to just carry on with the sounds of normal life. There’s no reason to avoid a loud situation – whether it’s a concert you’ve been looking forward to for months or an especially raucous baby shower.
Loud noise does have the possibility to cause some developmental damage or hearing loss in the unborn baby when it’s continuous and repeated. If you’re exposed to loud noise in a factory for eight hours a day, it’s a good idea to talk to your boss about the possibility of transferring temporarily to a quieter setting.
What Happens If My Baby Has Hearing Loss?
Shortly after birth, newborns are given a hearing screen designed to pick up the hearing loss in infants. This is a simple test that is done while the baby is sleeping. If the results of the screen are not normal, an audiologist will then perform a thorough diagnostic hearing test.
The audiologist will also test the baby while it is asleep. This will identify if the baby has hearing loss. If your baby has been exposed to loud noise, a high-frequency hearing loss may be found.
If a hearing loss is detected, the audiologist will explain how severe the hearing loss is and what type of hearing loss is found. The audiologist will guide you to seek the best early intervention and treatment for you and your baby.
Hearing loss may require the prompt fitting of hearing aids by an audiologist to give your baby the best chance of developing speech and language appropriately. If you think your baby may have hearing loss, talk to your audiologist right away. Early treatment for hearing loss is important for your baby’s health and development.
How Do Audiologists Test Your Baby’s Hearing?
If your baby fails the newborn hearing test, you will be asked to bring your child to see an audiologist. The audiologist will perform several automatic hearing tests. These hearing tests do not cause any discomfort to your baby.
While your baby sleeps, the audiologist will play some sounds directly into your baby’s ear and look for tiny electrical responses to these sounds. The audiologist will use tiny insert earphones and stickers (electrodes) on your baby.
The audiologist will undertake a range of tests, including:
- ABR – auditory brainstem response
- ASSR – auditory steady-state response
- OAE – otoacoustic emissions
- Tympanometry – a pressure test to see how the eardrum is moving.
The paediatric audiologist is specially trained to interpret the results and will explain them to you.
Signs of Hearing Loss In Babies
Signs of hearing loss in your baby can include:
- Not being startled by loud noise
- Not turning toward a sound or loud noise after 6 months
- Not saying simple words like “mama” or “dada” by the age of 1 year old
- Seems to hear some sounds but not others
If your child shows signs of hearing loss at any time, call your local audiologist to get your child’s hearing checked. Your audiologist can test your baby’s hearing, diagnose any hearing problems and plan treatment accordingly. Don’t hesitate to book your appointment today!