Also called Mongolian spots, they are a type of birthmark caused by pigment in the skin.
The medical term for a pigmented birthmark, such as a Mongolian spot, is congenital dermal melanocytosis .
Mongolian spots are often present at birth, but they can also appear in the first weeks of the baby’s life. These birthmarks have been known for centuries, and people used to attribute them to myths and cultural beliefs.
Mongolian spots cannot be prevented, and experts don’t know why some babies get them and others don’t.
They occur when some of the pigment in the skin becomes “trapped” in the deeper layers of the skin during the baby’s development. When the pigment does not reach the surface, it appears as a gray, greenish, blue or black mark.
Fast facts on Mongolian spots
In 1885, the term Mongolian spots was coined by a German professor named Edwin Baelz, who believed that Mongols and non-Caucasians were the only ones who developed these marks.
Some people thought they were a “scourge” or slap from gods or other religious deities. Other people believed that they were caused by an act of the mother during pregnancy, such as sexual intercourse or work.
Mongolian spots, by themselves, do not pose any health risk. Most babies who have them will outgrow them and they won’t have any health effects.
What Causes Mongolian Spots?
Although no one knows for sure what causes Mongolian spots, some babies 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 occur equally in boys and girls.
The spots are flat and smooth and may look like bruises. But, unlike bruises, they are painless and are not the result of injury.
How common are Mongolian spots?
The American Academy of Pediatrics (AAP) says that at least 2 percent of babies are born with some type 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 example, 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 babies, and both had Mongolian spots.
Do Mongolian spots pose health complications?
Mongolian spots are more common in babies with darker skin than in lighter skinned ones.
Although typically harmless, in a small number of cases, Mongolian spots have been associated with a rare metabolic disease such as:
- Hurler’s disease.
- Hunter syndrome.
- Niemann-Pick disease.
The link may be more likely to occur in babies whose Mongolian spots are large, widespread, or in areas outside of the back and buttock regions.
An article in the World Journal of Clinical Cases indicates 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 says that a birthmark in the spinal area can be a sign of a spinal cord defect, but Mongolian spots are not included in this category.
The status of the organization only red birthmarks could have a possible spina bifida link.
Treatments for babies with Mongolian spots
Mongolian spots often fade on their own, but in some cases they will remain on the skin into adulthood.
A doctor should examine the newborn’s Mongolian spots and document them in the baby’s medical record. This record helps avoid possible suspicions of physical abuse at a later date if the birthmarks are mistaken for bruises.
Points can also be reviewed at regular wellness visits to determine if they will go away on their own as the child grows.
The AAP says that most Mongolian spots disappear completely by the time a child reaches 5 years old. In some cases, however, they do not fade, and a person may have the birthmark for life.
Because they typically affect the back and buttock area, Mongolian spots are usually not even considered a cosmetic problem. The American Society for Dermatological Surgery says that Mongolian spots do not require treatment.
However, for those who have Mongolian spots that persist into adulthood, removal procedures may be an option.
A small study in Losers in Medical Science found that some people tested positive 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 turns 20.
Additionally, the side effects of skin darkening are minimized if laser treatments are timed correctly.
A combination of other types of lasers and a skin whitening cream can work well in conjunction with the alexandrite laser.
Mongolian spots are considered harmless, even with their possible link to the rare disorders mentioned above. If the baby has been checked by a medical professional and he has no health problems, the spots should not be a 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 seek cosmetic removal options. The decision is up to the person and their healthcare team.