Pediatric hearing screening - A guide for parents

Hearing before birth

Babies can hear even before they are born. The auditory system is fully developed at around 25 weeks of pregnancy^[1]. Globally, 34 million children have hearing loss, 60% of which are due to preventable causes^[2]. Healthy hearing is essential for a child's overall development, including language acquisition, communication, social skills, and academic performance^[2]. Early identification and intervention of hearing impairments can prevent long-term adverse effects, making pediatric hearing screening a key step in detecting hearing issues early^[3].

The impact of hearing loss during infancy

Unaddressed hearing loss, especially when present at birth or acquired early in life, significantly impacts a child's development in areas such as language, cognitive abilities, social skills, education, and future vocational opportunities^[3]. There is compelling evidence^[2] that newborn hearing screening significantly reduces the age of diagnosis and intervention for permanent childhood hearing loss.

Why early detection is crucial

Children who undergo hearing screening early can receive timely diagnosis and intervention, which leads to enhanced overall development and improved quality of life compared to children who don't receive hearing screening.

Babies who are born with hearing loss, who are identified before 3 months of age, and receive intervention by 6 months of age, can reach comparable speech-and language outcomes to their peers with normal hearing.^[3]. The goal of early detection of hearing loss is to optimize the perception of speech and the development of language skills. Identifying new or progressive hearing loss in one or both ears, followed by appropriate referral for diagnosis and treatment, is the first step to minimizing the negative effects of untreated hearing loss ^[4].

When should hearing screening take place? Parents of newborns are medically advised to undergo hearing screenings before leaving the hospital or birth center^[3]. If this does not happen, parents should immediately schedule an appointment with an audiologist. Early screening is essential to prevent compromised hearing health, which can lead to more severe developmental issues later on.

When and how screening is conducted ^{[4; 5; 6]}

Pediatric hearing screening is conducted at various stages of a child’s development to ensure early detection and intervention of hearing issues. The section below explains what you can expect at each stage:

• Newborn screening: Early screening helps identify congenital hearing loss, which is present from birth. If hearing screening is not offered as part of the routine newborn screening assessments before discharge from the hospital, parents are advised to request the service, or book an appointment at the 6-week immunization visit
• Follow-up screenings: If a newborn fails the initial screening, follow-up tests are conducted to confirm the presence of hearing loss. For babies admitted to the neonatal intensive care unit (NICU), there may be a need for more frequent screenings every three months following hospital discharge. This is to monitor for progressive hearing loss, especially in cases where certain treatments, such as for jaundice or meningitis, might cause hearing loss due to ototoxicity (side effects from medications that can damage hearing).
• Regular check-ups: Pediatricians often include hearing screenings during regular check-ups. These are especially important at key developmental milestones, such as at 6 months, 1 year, and annually thereafter. These screenings help track a child’s hearing over time and detect any changes early. In addition, young children are prone to middle ear infections, and regular hearing screenings can detect conductive loss due to fluid build-up in the middle ear, which may also negatively affect speech- and language acquisition.
• School screenings: Schools often conduct hearing screenings to identify any issues that may develop later in childhood. These screenings are usually performed by an audiologist or trained school nurses. Regular school screenings can help to ensure that any hearing problems that arise can be addressed promptly, supporting the child’s academic and social development.

Stages of childhood and corresponding hearing tests ^{[4; 5; 6]}

Newborn stage (0-1 month)

Hearing Screening for Infants (Newborn to 3 years of age)

• Otoacoustic Emissions (OAE): A tiny probe that plays soft sounds is placed in an infant's ear. This assessment helps to establish the inner ear's response to sound. The assessment is quick, non-invasive and doesn't cause any discomfort for the infant undergoing the assessment.
• Automated Auditory Brainstem Response (AABR): This test uses automated equipment for screenings, and evaluates the response of the hearing nerve and brain to sound. It is non-invasive and painless.

Infant stage (1 month - 1 year)

Hearing testing

• Auditory Brainstem Response (ABR): Small sensors are placed on the infant's head to measure how the hearing nerve and brain responds to sounds played through earphones. This assessment is typically done if the AABR screening fails.
• Behavioral audiometry: This test observes the baby's reactions to different sounds, such as turning their head or responding to noisy toys. It is simple and non-invasive, relying on natural responses.
• Visual Reinforcement Audiometry (VRA): Sounds are played, and the toddler is trained to look towards the sound source. When they respond correctly, they are rewarded with visual stimuli like lights or animated toys. This test is non-invasive and engaging for the child. Validated parental questionnaires are also available during the infant stage, to monitor auditory development.

Toddler stage (1 - 3 Years)

Hearing test: Visual Reinforcement Audiometry (VRA)

• Tympanometry: A small device measures the movement of the eardrum in response to changes in air pressure. This test helps detect issues like fluid in the middle ear. It might cause a slight feeling of pressure but is generally well-tolerated and quick.
• VRA assessment is used.
• Speech audiometry: The child listens to speech presented at different volumes through headphones to assess their ability to hear and understand speech by pointing to pictures.

Preschool stage (3 - 5 years)

Hearing test: Play audiometry

• Play audiometry: The child is asked to perform a simple task, such as putting a block in a bucket each time they hear a sound. This test makes hearing screening fun and keeps the child focused. It is non-invasive and enjoyable. Different tones are used to get an indication of a child’s hearing profile across different frequencies.
• Speech audiometry can also be used.

School age (5 years and older)

Hearing test: Conventional audiometry

• Conventional audiometry: The child wears headphones and raises their hand or presses a button each time they hear a sound. This test checks a range of frequencies and volumes to assess hearing ability. It is non-invasive and straightforward.
• Otoacoustic Emissions (OAE) and Tympanometry: These tests may be used to gather additional information about the child's hearing health and middle ear function.
• Speech audiometry can be used at the school stage as well.

Objective vs. Behavioral tests ^[7]

• For younger children or those who cannot provide reliable responses, objective tests such as OAE and ABR are used. These tests do not require any response from the child and provide reliable results.
• As children age, behavioral tests, which require the child to actively respond to sounds, become the gold standard for assessing hearing. These behavioral tests are more accurate in gauging how well a child can hear in different environments and situations.

What to expect during the hearing screening process ^{[7; 8]}

Preparation

• Ensure comfort: Make sure your child is well-rested and has eaten before the screening. This helps to keep them calm and cooperative.
• Explain the process: For older children, explain the screening process in simple terms to reduce any anxiety they might feel.

During the test

• Newborns: The screening is often done while the baby is asleep. This allows for a smoother and more accurate assessment.
• Older children: The tests may involve wearing headphones and responding to various sounds by raising their hand or pressing a button. None of the hearing tests are invasive and should not cause any source of pain or discomfort.

Duration

• Screening tests are usually quick and can be conducted within minutes however, may take longer in some cases when there may be interference with the test stimuli such as background noise, or lack of cooperation from the child.

Results

*Immediate feedback: In most cases, you will receive the results immediately after the screening. If the results indicate potential hearing loss, further diagnostic tests will be recommended.

Screening vs. diagnostic testing ^[10]

• Screening: A hearing screening identifies individuals who may need a more comprehensive hearing assessment and/or medical management. If a child does not pass the screening, it is called a 'refer' result. This does not necessarily mean the child has a hearing loss; it could indicate a temporary issue such as an ear infection, ear wax buildup, or the need for a retest.
• Diagnostic testing: A confirmation of the type and degree of hearing loss can only be made after a full battery of diagnostic tests have been conducted.

Interpreting the results and next steps ^[4;10]

If the screening indicates potential hearing loss, follow-up with further diagnostic testing is critical. These tests confirm the extent and type of hearing loss, allowing for the development of an appropriate intervention plan. Possible interventions include: - Medical management: In the event that there are any medical conditions preventing the child from hearing within normal limits, the child will be referred to an Otolaryngologist also known as an Ear, Nose, and Throat Specialist (ENT) for medical intervention, prior to any further audiological intervention. An example could be the presence of recurrent ear infections which could in some cases be resolved with the insertion of grommets. - If there are no medical concerns present and the child presents with a permanent hearing loss, then audiological interventions such as hearing aids and cochlear implants will be considered to assist the child in hearing better. The audiological intervention is comprehensive and generally includes a referral for speech and language therapy and educational support, along with aural rehabilitation (a combination of strategies to help individuals with hearing loss improve their communication abilities and quality of life) and counseling.

Importance of early intervention ^{[11;12;13; 14]}

Children with hearing loss have the greatest potential for language development when interventions start early, ideally before the age of three, as this is when the brain's ability to form connections is most optimal. From age seven, neural or brain plasticity significantly declines. Early introduction to sound during this critical period allows the brain to adapt to auditory processes and integrate them meaningfully. Since children with hearing loss miss out on sound exposure from the development of their auditory system in utero until the period when amplification is received, it's essential to catch up on this sound exposure to achieve age-appropriate developmental milestones. This should happen in conjunction with rigorous aural rehabilitation for optimal outcomes. Increased language exposure at home, daycare, and in the community facilitates better language skill development in children with hearing loss.

FAQ: “If my newborn's hearing is fine, will they need to be screened later?”

Yes, routine hearing tests are essential for all children because hearing can change significantly as they grow. Common causes of childhood hearing changes include ^{[15, 16]}:

• Frequent ear infections.
• Measles or meningitis.
• Head injuries.
• Exposure to loud noises.
• Second-hand smoke.

Additionally, newborns who spend extended periods in a neonatal intensive care unit (NICU) may face higher risks for hearing changes later in life^[17].

The American Academy of Pediatrics (AAP) recommends hearing tests at ages 4, 5, 6, 8, and 10 years, with additional screenings at ages 11-14, 15-17, and 18-21 ^{[9; 17]}. These screenings can diagnose hearing changes at the earliest possible stage, allowing interventions to have the greatest positive impact. Your pediatrician or audiologist may recommend a different screening schedule if there is a family history of hearing changes or environmental factors that could affect your child's hearing. Consistent screening is important as hearing changes can be very gradual and hard to notice initially. Regular tests help ensure any issues are identified early, allowing your child to receive the necessary care and support.

Hearing at home: Signs to watch for in your child ^{[18; 19]}

Parents, caregivers and teachers are often the first to notice changes in a child's hearing. If you observe any of the following signs, consult your hearing healthcare professional:

• Doesn't startle at loud noises.
• Does not turn toward sounds.
• Is slow to begin talking or their speech is difficult to understand.
• Cannot say single words like "dada" or "mama" by 12 to 15 months.
• Does not notice you until they see you.
• Focuses on vibrating noises more than other sounds.
• Shows no enjoyment or pleasure when you read to them.
• Does not always respond when called, especially from another room.
• Appears to hear some sounds but misses others.
• Wants the music or TV volume louder than other family members.

What to do if your baby did not have a hearing screening at birth ^[20]

If your baby did not have a hearing screening at birth, schedule an appointment with an audiologist as soon as possible. Early detection is imperative for timely intervention, which supports language development and overall learning.

The importance of formal hearing tests ^[9]

Formal hearing tests are vital even if your baby reacts to sounds, as apparent responses do not always indicate clear hearing. Undetected hearing issues can hinder early language development, impacting future academic and life success. Additionally, mild hearing loss can go unnoticed initially, as children may respond to some sounds and develop speech. Children are also susceptible to ear infections, which, if untreated, can lead to permanent hearing impairment over time. Regular screening helps identify and address these concerns early.

Challenges in low- and middle-income countries (LMICs) ^[4]

Over the past two decades, Early Hearing Detection and Intervention (EHDI) programs have been mandated in several high-income countries (HICs), based on guidelines and standards provided by the Joint Committee on Infant Hearing, the WHO, the American Audiology Association, the Newborn Hearing Screening Programme England, and the European Consensus Statement on Neonatal Hearing Screening ^[21].

In 1995, the World Health Organization (WHO) adopted a resolution urging member states to create national plans for the prevention and control of major causes of avoidable hearing loss and for the early detection of hearing loss in babies, toddlers, and children. However, by 2012, only 32 countries had reported implementing such policies, and the WHO noted a significant lack of epidemiological and other data regarding ear and hearing care (EHC). A second WHO resolution in 2017 reaffirmed these aims and called on member states to collect high-quality, population-based data on hearing loss and ear diseases ^[21].

In low- and middle-income countries (LMICs), newborn hearing screening is not universally mandated, facing numerous implementation challenges^[3]. These include limited access to equipment, financial constraints, shortages of healthcare professionals, heightened risks of hearing loss from environmental factors, low awareness levels, and high disease rates.

Facilitating access to hearing health technology

To heed the call of hearing care accessibility, hearX® Group has developed solutions to address the obstacles mentioned previously. Our flagship product hearScreen®, was originally designed to assist with conducting hearing screenings at schools and it has proven adaptable to diverse resource-limited settings due to its user-friendly features. In addition, we’ve recently added hearOAE to our suite of solutions, using similar principles to address the challenges in objective testing and the device can also be used in various settings. Portable audiometry has evolved significantly, now serving as an invaluable tool for facilitating accessible hearing assessments in both LMICs and high-income countries alike.

HearX Foundation (hXF), a nonprofit organization we established in 2016, aims to minimize the adverse effects of untreated hearing loss in underserved communities within South Africa. hXF runs programs at the grassroots level to identify hearing loss and facilitate timely intervention. They use our flagship solutions, which include hearScreen, hearScope, and hearTest, to support community hearing health programs. One notable initiative, the 3E Project (Ears and Eyes for Education), focuses on hearing screening in children, providing access to hearing care at early childhood development centers (ECDs) and preschools. This ensures that hearing loss is identified before children formally start attending school, giving them a better chance of academic success.

Conclusion

Pediatric hearing screening is a critical step in ensuring a child's healthy development. Early detection and intervention can significantly impact a child's language, social, emotional, and academic development. As a parent, understanding the importance of hearing screening and being informed about the process can help ensure your child receives the necessary care and support.

hearX cares, which is why we’ve developed technologies that facilitate accessibility and affordability to hearing health. If you have any questions or concerns about your child’s hearing, ask your audiologist, school or healthcare practitioner about hearX and how to get your child tested.