If an infant is born with a missing ear, the condition is called anotia. If the ear is smaller than average or only a portion of the ear developed, it is called microtia.
The ear develops completely in utero during healthy gestation. In some cases, at birth the ear is smaller than average, partially developed or missing all together.
Anotia is extremely rare and hardly ever reported. Microtia is much more common. There are four grades of the condition:
Grade I: Ear is slightly smaller than normal, but all structures can be identified.
Grade II: Part of the ear has developed, but the ear canal is blocked and hearing lost.
Grade III: External ear, external ear canal and ear drum are missing. A small bump of tissue is present.
Grade IV: Anotia or no ear tissue or internal structures.
Treatments for the condition will depend on how severe the microtia is at birth. In some cases, the ear canal can be rebuilt and hearing restored with the help of a hearing aid.