What is microtia?

Microtia is a deformity of the outer ear. This deformity can range from mild structural problems to a completely missing external ear. When accompanied by a missing ear canal it also can cause hearing problems and difficulty telling which direction a sound comes from.

Microtia usually affects one ear but can occur in both ears. It usually develops during the first trimester of pregnancy.

How common is microtia?

Doctors diagnose microtia in roughly 1 to 5 out of 10,000 births. The condition occurs more often in boys than girls. It affects the right ear more often than the left.

What are the risk factors for microtia?

Babies at a higher risk for microtia include those whose mothers:

  • Are over age 35
  • Become acutely ill during pregnancy
  • Do not get enough carbohydrates or folic acid during pregnancy
  • Have diabetes
  • Have given birth to a child with the condition
  • Used certain medications including isotretinoin (Accutane®) while pregnant

Symptoms and Causes

What causes microtia?

Doctors do not know what causes most cases of microtia. It usually develops during the first trimester of pregnancy.

In some cases, microtia is a feature of a larger syndrome such as craniofacial microsomia (a condition that affects the development of the face before birth). Some cases of microtia are genetic (passed down among family members).

What are the symptoms of microtia?

The symptoms of microtia include:

  • Abnormally formed outer ear
  • Missing outer ear (anotia)
  • Smaller than normal ear size

Diagnosis and Tests

How is microtia diagnosed?

A doctor usually diagnoses microtia at birth. The deformity is visible when the baby is born. Sometimes a doctor uses an imaging test called a CT scan to get a detailed picture of the baby’s ear. This test helps the doctor look for abnormalities of the ear bones of the middle ear.

There are several classification systems. The severity of the deformity determines the type and can be classified as:

  • Type 1: External ear is smaller than average but all parts are present with minor deformities
  • Type 2: Outer ear is partially formed and small
  • Type 3: Some auricular structures but no recognized ear parts
  • Type 4: Anotia (complete absence of external ear)

Management and Treatment

How is microtia managed or treated?

The external appearance of microtia does not always require treatment, but any hearing loss should be addressed. It is very important to obtain hearing evaluation early and maintain close hearing follow-up through early childhood.

If patients and families choose to address the microtia there are several options. One is by using a prosthesis (made of a silicone material). These can look very natural and may attach with adhesive or magnets. However, they require maintenance over time and may not be the best option for some children.

Other options included surgery to reconstruct the affected ear. Reconstructive surgery can begin between ages 6-9 depending on techniques used, and there can be two to four stages involved in this reconstruction. During this process, doctors create a new ear from cartilage collected from the rib or from synthetic (human-made) materials.

What complications are associated with microtia?

Hearing loss is the most common complication associated with microtia. Some people with microtia feel embarrassed or have self-esteem issues caused by the ear’s appearance.


Can microtia be prevented?

Steps women can take to reduce their risk of having a baby with microtia include:

Outlook / Prognosis

What is the prognosis (outlook) for people with microtia?

Many children with microtia have otherwise normal development and lead active and healthy lives. Hearing can be improved or restored in most patients with microtia.

Living With

When should I call the doctor?

Women who are pregnant or want to become pregnant should talk with their doctor about how to increase their chances of having a healthy baby. A woman who had one baby with microtia has a small risk of having another child with the condition.

What questions should I ask my child’s doctor?

If your child has microtia, you may want to ask your doctor:

  • How severe is the deformity?
  • What signs of complications should I look out for?
  • What is the best treatment for my child?
  • Who should I see to ensure my child’s hearing is optimized?

When can my child go back to regular activities?

The time around surgery is the only time when a child living with microtia might have restrictions on their activities.

Recovery after treatment for microtia depends on the treatment involved. Your doctor will tell you when it is safe for your child to resume normal activities.

Last reviewed by a Cleveland Clinic medical professional on 02/11/2019.


  • Centers for Disease Control and Prevention. Facts about Anotia/Microtia. (https://www.cdc.gov/ncbddd/birthdefects/anotia-microtia.html) Accessed 6/26/2020.
  • EarCommunity.org. Microtia & Atresia. (https://earcommunity.org/microtiaatresia/) Accessed 6/26/2020.
  • FACES: The National Craniofacial Association. Microtia. (https://www.faces-cranio.org/microtia) Accessed 6/26/2020.
  • Luquetti D, Heike C, Hing A, Cunningham M, and Cox T. Microtia: Epidemiology & Genetics. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3482263/) Am J Med Genet A. 2012 Jan; 158A(1): 124–139. Accessed 6/26/2020.

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