Milia are tiny white bumps or small cysts on the skin that are almost always seen in newborn babies.
Milia occur when dead skin becomes trapped in small pockets at the surface of the skin or mouth. They are common in newborn infants.
Similar cysts are seen in the mouths of newborn infants. 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 swollen (inflamed) or injured. Irritation of the skin by rough sheets or clothing may cause mild reddening around the bump, but the middle stays white.
Irritated milia are sometimes incorrectly called "baby acne," although it is not actually a form of acne.
The doctor can usually diagnose milia just by examining the skin or mouth. No testing is needed.
In children, no treatment is needed. Skin changes on the face or cysts in the mouth usually disappear after the first few weeks of life without treatment, and without any lasting effects.
A doctor may remove milia in adults who want to improve their appearance.
There is no known prevention.
Morelli JG. Diseases of the neonate. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 18th ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 646.