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

What can cause Microtia?

Microtia usually develops during the first trimester of pregnancy, in the early weeks of development. Its cause is mostly unknown but has sometimes been linked to drug or alcohol use during pregnancy, genetic conditions or changes, environmental triggers, and a diet low in carbohydrates and folic acid.

What are the odds of having Microtia?

Microtia occurs about 1 in 5,000 births, though rates can vary depending on ethnic background. In 90% of cases, it affects only one ear, usually the right ear, and is more common in males.