Microtia/Atresia of the Ear
Content reviewed against published CDC, NIH guidelines
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If your baby has been diagnosed with or you suspect microtia/atresia of the ear, here is what the evidence says.
The short answer
Microtia is a congenital condition where the outer ear (pinna) is underdeveloped, and atresia is the absence or closure of the ear canal. They often occur together. Microtia affects approximately 1 in 5,000-7,000 births and is usually unilateral (one ear). While the appearance is the most visible concern, the primary medical consideration is hearing - atresia causes conductive hearing loss on the affected side. Early hearing evaluation and intervention are important. Reconstructive surgery is typically an option when the child is older.
Key takeaways
- Microtia is a congenital condition where the outer ear (pinna) is underdeveloped, and atresia is the absence or closure of the ear canal. They often occur together. Microtia affects approximately 1 in 5,000-7,000 births and is usually unilateral (one ear). While the appearance is the most visible concern, the primary medical consideration is hearing - atresia causes conductive hearing loss on the affected side. Early hearing evaluation and intervention are important. Reconstructive surgery is typically an option when the child is older.
- Usually normal when: Your baby has mild microtia (a slightly smaller or differently shaped ear) with a normal ear canal and normal hearing - many variations of ear shape are benign.
- Call your doctor if: Your baby has bilateral microtia/atresia (both ears affected) and has not yet been fitted with bone conduction hearing devices - bilateral hearing loss requires urgent intervention for language development.
- Varies by age — see the age-by-age breakdown below
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By Age
What to expect by age
0-3 months
Microtia/atresia is identified at birth. Your newborn should receive comprehensive hearing testing (ABR) to assess both ears. Even with one normal ear, monitoring is important. If both ears are affected, hearing intervention is urgent. A bone conduction hearing device (such as a softband with a bone conduction processor) can be fitted within the first few months of life to provide hearing while the ear canal is absent. Your pediatrician may also check for associated conditions affecting the jaw, kidneys, or spine.
3-6 months
If a bone conduction device was recommended, your baby should be wearing it consistently by now. For unilateral microtia with a normal opposite ear, your baby may develop speech normally using the hearing ear, but the affected ear should still be monitored. Your medical team (ENT, audiologist, possibly craniofacial specialist) will outline a long-term plan. Ear mold prosthetics are not typically used at this age.
6-12 months
Continue consistent use of any hearing devices. Speech and language development should be monitored closely, especially if hearing is affected bilaterally. Your child should be enrolled in early intervention services if there are any hearing or speech concerns. The team may begin discussing future surgical options, although reconstruction is not performed this young.
12 months+
Toddlers with unilateral microtia and normal hearing in the other ear typically develop speech well but may have difficulty localizing sounds or hearing in noisy environments. Ear reconstruction surgery (using rib cartilage or synthetic frameworks) is typically performed between ages 6-10 depending on the technique. Atresiaplasty (surgically opening the ear canal) may be considered if the anatomy is favorable, usually around age 5-6. Your ENT and audiologist will guide the best timing and approach for your child.
What Should You Do?
When to take action
- Your baby has mild microtia (a slightly smaller or differently shaped ear) with a normal ear canal and normal hearing - many variations of ear shape are benign.
- Your baby has unilateral microtia and is developing speech and language normally using the hearing ear.
- Your child with microtia is wearing a bone conduction hearing device and making good progress with hearing and speech.
- Your baby's ears appear slightly asymmetric - mild ear asymmetry is very common and different from microtia.
- Your baby was born with a noticeably small or underdeveloped ear and has not yet had a complete hearing evaluation.
- Your child with known microtia/atresia is having difficulty with speech development or hearing in group settings.
- You have questions about the timing or options for surgical reconstruction.
- Your baby has bilateral microtia/atresia (both ears affected) and has not yet been fitted with bone conduction hearing devices - bilateral hearing loss requires urgent intervention for language development.
- Your child with microtia develops new symptoms such as ear drainage, pain, or sudden change in hearing in either ear.
Doctor Visit Checklist
Bring this checklist to your next pediatrician visit to discuss Microtia/Atresia of the Ear.
Things to mention
- Your baby was born with a noticeably small or underdeveloped ear and has not yet had a complete hearing evaluation.
- Your child with known microtia/atresia is having difficulty with speech development or hearing in group settings.
- You have questions about the timing or options for surgical reconstruction.
Observations to share
- Your baby was born with a noticeably small or underdeveloped ear and has not yet had a complete hearing evaluation.
- Your child with known microtia/atresia is having difficulty with speech development or hearing in group settings.
- You have questions about the timing or options for surgical reconstruction.
Urgent signs to report immediately
- Your baby has bilateral microtia/atresia (both ears affected) and has not yet been fitted with bone conduction hearing devices - bilateral hearing loss requires urgent intervention for language development.
- Your child with microtia develops new symptoms such as ear drainage, pain, or sudden change in hearing in either ear.
My notes
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Frequently asked questions
Is microtia/atresia of the ear normal?
When should I call the doctor about microtia/atresia of the ear?
When is microtia/atresia of the ear normal?
What causes microtia/atresia of the ear?
What should I mention to my pediatrician about microtia/atresia of the ear?
Is microtia/atresia of the ear normal at 0-3 months?
Is microtia/atresia of the ear normal at 3-6 months?
Should I go to the ER for microtia/atresia of the ear?
Does microtia/atresia of the ear go away on its own?
References
All content follows our editorial policy and is reviewed against published clinical guidelines.
2,705 evidence-based guides6 authoritative medical sources
Related Resources
Bottom line
Most cases of microtia/atresia of the ear are normal. Talk to your pediatrician if your baby has bilateral microtia/atresia (both ears affected) and has not yet been fitted with bone conduction hearing devices - bilateral hearing loss requires urgent intervention for language development.
Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.
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