Mongolian spots are a type of birthmark caused by the pigment in the skin. The medical term for a pigmented birthmark such as a Mongolian spot is a congenital dermal melanocytosis.
Mongolian marks are often present at birth, but may also appear in the infant’s first weeks of life. These birthmarks have been known about for centuries, and people used to attribute them to cultural beliefs and myths.
Mongolian spots cannot be prevented, and experts do not know why some babies get them and others do not.
They occur when some of the skin’s pigment gets “trapped” in the deeper layers of skin during the infant’s development. When the pigment does not reach the surface, it appears as a gray, greenish, blue, or black mark.
While no one knows for sure what causes Mongolian spots, some infants are more likely to get them than others; particularly those with darker skins, such as those of Asian, Hispanic, Native American, African, and East Indian descent.
Mongolian spots usually occur on the back and buttock area and happen equally in boys and girls.
The marks are flat and smooth and may look like bruises. But, unlike bruises, they do not cause pain and are not a result of an injury.
The American Academy of Pediatrics (AAP) says at least 2 percent of babies are born with some form of pigmented birthmark, including Mongolian spots, moles, and café-au-lait spots.
But, some studies show much higher numbers, particularly those that take into account more people of color. For instance, an article in the Indian Journal of Dermatology, Venereology, and Leprology cites studies that identify Mongolian spots in 9.5 percent of Caucasian babies, 46.3 percent of Hispanic babies, and 96.5 percent of black babies.
The study included only two Asian infants, and both had Mongolian spots.
Though typically harmless, in a small number of cases, Mongolian spots have been associated with a rare metabolic disease such as:
- Hurler’s disease
- Hunter’s syndrome
- Niemann-Pick disease
The link may be more likely to occur in babies whose Mongolian spots are large, widespread, or on areas outside of the back and buttock regions.
An article in the World Journal of Clinical Cases states that these rare disorders, as well as a spinal cord malformation known as occult spinal dysraphism, could be related to Mongolian spots – but more research is needed.
The Spina Bifida Association say a birthmark on the spine area can be a sign of a spinal cord defect, but Mongolian spots do not fall under this category. The organization state only red birthmarks could have a possible link spina bifida.
A doctor should examine the newborn’s Mongolian spots and document them in the baby’s medical record. This record helps avoid possible suspicion of any physical abuse at a later date if the birthmarks are mistaken for bruises.
The spots can also be checked at regular well-child visits to determine whether they are going away on their own as the child grows.
The AAP say most Mongolian spots disappear completely by the time a child reaches age 5. In some cases, however, they do not fade, and a person may have the birthmark for life.
Do Mongolian spots require treatment?
Mongolian spots do not need any special care. They are not painful and do not pose any problems with the skin.
Because they typically affect the back and buttock area, Mongolian spots are usually not even considered to be a cosmetic issue. The American Society for Dermatologic Surgery says Mongolian spots require no treatment.
However, for those who have Mongolian spots that persist into adulthood, removal procedures may be an option.
A small study in Lasers in Medical Science found that some people achieved positive results with a device called an alexandrite laser.
Another study in Dermatologic Surgery found that Mongolian spots are most successfully treated with the alexandrite laser before the individual reaches age 20. Also, the skin darkening side effects are minimized if the laser treatments are timed properly.
A combination of other types of lasers and a skin bleaching cream may work well in conjunction with the alexandrite laser.
Mongolian spots are considered to be harmless, even with their possible link to the rare disorders listed above. If the baby has been checked by a medical professional and has no health issues, the spots should not be cause for concern.
People who have Mongolian spots, whether they outgrow them or have them for life, live normal, healthy lives.
As with any birthmark, people with Mongolian spots may decide to accept their appearance or look into cosmetic removal options. The decision is up to the individual and their healthcare team.