Mongolian or blue spots Congenital dermal melanocytosis (CDM) appears in some newborns at birth or in the first few weeks of life. It is called a "Mongolian spot" because it frequently appears on the skin. Asian, American Indian, African and Indonesian racesIt is present in a very high percentage of newborns of these breeds (reaching around the 90 % in some groups), while in Caucasians it only appears in a small percentage (1-5%), being somewhat less frequent.
The newborn's skin appears stained with a blue, blue-green or blue-gray tone, mainly in the area of ​​the back, buttocks and shoulders and, more rarely, on thighs, arms, feet, or other areas of the body. Its shape and size are highly variable, presenting blurred edgesThese characteristics often lead to it being confused with birth bruises (bruises) or even with possible signs of abuse if they are not well known.
What exactly is a Mongolian spot?
The Mongolian spot is a congenital hyperpigmentation of the skin. Its medical name is congenital dermal melanocytosis and it is considered the most frequent pigmented lesion in newborns of certain ethnicities. It is a flat birthmarkbluish, bluish-gray or slightly violet in color, which is already present at birth or appears during the first weeks of the baby's life.
Its origin is in a accumulation of melanocytes (cells responsible for the production of melanin and protection against the sun's rays in the skin). In Mongolian spots, these melanocytes are located in the deep dermis instead of being located at the junction between the epidermis and the dermis, as is usually the case.
The effects of light on these melanocytes, located deep within the dermis, are what give it that characteristic. characteristic bluish color, as a consequence of the so-called Tyndall effectAt that depth in the skin, red and yellow colors are not reflected, and what we visually perceive is a bluish or grayish tone.
Frequency and ethnic factors of Mongolian spots
La frequency of Mongolian spots It varies significantly among different racial groups. They are especially common in newborns of Asian, African, Native American and some Latin American originIn these babies, the presence of the Mongolian spot can reach very high percentages, around 90 % in certain populations.
In the population caucasian or those with fair skin, on the other hand, the incidence is much lower (approximately 1-5%), which is why it is a less well-known skin lesion that can generate more doubts and concerns in parents when it appears in their babies. Even so, it is still a disorder completely benign and with similar behavior across all ethnicities.
In addition, it has been observed that Mongolian spots can be slightly more frequent in males and in preterm newborns (babies born before completing gestation), although this difference has no impact on the baby's health or on the subsequent evolution of the spot.
What do Mongolian spots look like and where do they appear in newborns?
La most common location The Mongolian spot is the region lumbosacral and glutealThat is, the lower back and buttocks. However, it can also extend to the lumbar region, hips, or thighs. In other cases, they appear in areas considered atypicalsuch as the upper back, shoulders, arms, hands, feet, or even the scalp; these shapes are sometimes called aberrant Mongolian spot.
The skin appears stained with a blue, blue-green, blue-gray or violetThey are injuries flatThey are flat, and they don't hurt or itch. poorly defined or irregular edges and they can be single or multipleThe size varies greatly: from a few millimeters to more than 20 centimeters, being able to occupy a large area of ​​the baby's back or lumbar region.
These characteristics (bluish color, irregular shape, possibility of being extensive) mean that in many cases they can be mistaken for bruises from blows or bruising from childbirth. Unlike a hematoma, a Mongolian spot It doesn't change color over time.It does not hurt to the touch and usually remains stable or diminishes very slowly.
When does the Mongolian spot appear and how long does it last?
The Mongolian spot is usually present since birthalthough in some newborns it becomes more evident during the first weeks of lifeIn the first few months, the injury may even darken slightly or appear larger, reaching its maximum visibility during the first stage of childhood.
If our child has these spots, we should know that they are usually benign, They have no bearing on our baby's health y they will disappear spontaneously during the first few years of life. The birthmark usually begins to appear gradually lessen around age 2 And in most children, it becomes barely visible or almost imperceptible before adolescence. However, there are cases in which the spots are multiple, very extensive, or darkerAnd in some of these cases, the disappearance can be delayed until... 9 or 10 years or even persist into adulthood; this does not mean they are dangerous, but it may warrant a specialist assessment if they pose an aesthetic problem or cause concern.
Diagnosis: how to differentiate the Mongolian spot from other lesions
Mongolian spot in newborns is diagnosed in a clinicthat is, through a simple skin examination by the pediatrician. Generally, no additional tests are needed because its appearance, location, and evolution are very characteristic.
The features that help to distinguish the blue Mongolian spots Other alterations are mainly:
- Color bluish-gray, bluish or violet, homogeneous.
- Flat lesions, without relief or inflammation.
- Irregular or blurred edgesnot perfectly defined.
- Size usually larger than 2 cm, being able to reach large areas.
The pediatrician will take these characteristics into account in order to rule out other skin problems which also present with hyperpigmentation or change in coloration, such as some congenital nevi, vascular malformations o bruisesThis is especially important in the context of a possible suspicion of child abuseMongolian spots are painlessThey do not change color from day to day and persist for much longer than a common bruise.
Relationship with other syndromes and diseases
In the vast majority of cases, a Mongolian spot is a isolated condition with no pathological significanceHowever, some studies have described that when the spots are very extensive, multiple, intensely pigmented or are located in a very atypical way, they may be associated with rare metabolic syndromes and disorders.
Some of the diseases that have sometimes been linked to extensive Mongolian spots are certain congenital errors of metabolism (such as some mucopolysaccharidoses or gangliosidoses) and complex syndromes that include vascular or pigmentary malformations. In these cases, the spots usually cover large areas of the body and appear accompanied by other clinical signs such as muscle hypotonia, visceromegaly or other visible alterations in the examination.
It is important to emphasize that these associations are exceptionalThe presence of a typical Mongolian spot, located in the lumbosacral region and without other accompanying symptoms, does not in itself indicate any serious illness. The pediatrician will assess whether the spot presents characteristics that warrant further investigation.
Baby skin treatment and care
Once the child health specialist has diagnosed the presence of these spots and confirmed that it is a typical congenital dermal melanocytosis, No specific treatment is necessary. nor special monitoring, since, as we mentioned, they will disappear on their own as our son grows up.
Under normal conditions, the Mongolian spot does not need creams, medications, laser nor other therapies. Laser use is reserved only for very specific situations, generally for persistent blemishes in adulthood that pose an aesthetic problem for the individual. In childhood, the most advisable course of action is simply observe its natural evolution without intervening.
What is advisable is to maintain a good baby skincare routineA newborn's skin is very delicate, so it's always preferable to use... gentle baby cosmetic products, with respectful ingredients These treatments help protect and soothe the skin. They don't change the Mongolian spot, but they help keep the skin healthy and well-hydrated overall.
Therefore, although Mongolian spots do not require special care, it is important to maintain the clean, dry and protected areaJust like the rest of the baby's skin, use age-appropriate products and avoid aggressively rubbing the pigmented areas.
It's always a good idea to consult with the pediatricianwhich will confirm the presence of this birthmark, will explain its expected evolution And it will reassure us about her. Once the diagnosis is established, it will be enough to observe how she progresses. becoming clearer over timeRemembering that it is part of the many normal peculiarities of newborn skin.
Understanding what Mongolian spots are, how they appear, and how they evolve allows families to live with them more effectively. tranquilityAvoiding unnecessary worries and misunderstandings, and focusing on what matters most: enjoying the baby's first months of life and taking care of their skin in a comprehensive and respectful way.