Mongolian spot

Mongolian spots are blue-grey markings of the skin that usually affect the lower back and buttock region of newborn babies They are a common form of birthmark and are properly called congenital dermal melanocytosis.

What do they look like?

Mongollian spots are bluish-grey patches found on the lower back or buttocks. Aberrant Mongolian spots involve unusual sites such as the face or limbs. They are usually a few centimetres in diameter but larger ones may occur. The affected skin is not thickened or changed in any way other than in colour.

Mongolion spot

How do you get them and who is at risk?

Mongolian spots are thought to be due to entrapment of melanocytes (pigment cells) in the dermis that have failed to reach their proper location in the epidermis in the developing embryo.

They are present at birth and occur in more than 90% of children of Mongoloid race (e.g. East Asians, Polynesians, Indonesians, Micronesians). They occur less frequently in other races.

What treatments are available?

Mongolian spots are benign lesions that require no treatment. Usually they spontaneously disappear by the time the child reaches 4 years old. Persistent Mongolian spots may be larger and persist for many years.