Definition of Milia:

Milia are tiny white bumps or small cysts on the skin.

Causes, incidence, and risk factors:

Milia occur when dead skin becomes trapped in small pockets at the surface of the skin or mouth. They are common in newborn infants and appear as pearly white bumps, most commonly across the upper cheeks, nose, and chin. Milia generally disappear after the first several weeks of life.

Similar cysts are seen in the mouths of newborn infants. In this case, they are called Epstein's pearls. These cysts also go away on their own.

Adults may develop milia on the face. The bumps and cysts also occur on parts of the body that are inflammed or injured. Irritation of the skin by rough sheets or clothing may cause mild reddening around the bump, but the central portion remains white.

Irritated milia are sometimes incorrectly referred to as "baby acne" (although it is not actually a form of acne).