Nearly everyone has moles, which usually appear after birth.
Mongolian spots are more commonly seen in darker-skinned populations.
Each type of birthmark has its own appearance:
Cafe-au-lait spots are light tan, the color of coffee with milk.
Moles are small clusters of colored skin cells.
Mongolian spots (also called Mongolian blue spots) are usually bluish or bruised-looking. They usually appear over the lower back or buttocks, but can also appear in other areas, including the trunk or arms.
Large moles that are present at birth (congenital nevi) are more likely to become skin cancer (malignant melanoma). This is especially true if the mole covers an area larger than the size of a fist. The cancer risk is related to the size, location, shape, and color of the mole.
Mongolian spots may persist for months or years. They do NOT become cancer or develop other symptoms.
Psychological effects, if the birthmark is prominent
Calling your health care provider
Have any birthmarks examined by a health care provider. Report any changes in the birthmark to your health care provider, including:
Open sore (ulceration)
There is no known way to prevent birthmarks. A person with birthmarks should use a good quality sunscreen when outdoors (to prevent complications).
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.
Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.