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Blue-gray spots can appear on your child’s skin at birth or within the first few weeks. These spots, known as slate grey nevi, typically disappear by the child’s fifth birthday, but can last into adulthood. If your child is born with these spots, should you be worried? This birthmark generally poses no danger to your child, but you may want to be aware of certain factors surrounding this condition. Here is everything you need to know about slate grey nevi.

Slate Grey Nevi Causes

During an infant’s development, skin pigment cells can get trapped in the deeper layers of skin. This trapped pigment appears as colored marks on the skin. They can appear as gray, green, blue or black marks. The color of the birthmark is typically determined by the amount of melanin in the skin. This condition is more likely to affect people with darker skin. It is most commonly noticeable on both boys and girls of African, Native American or Asian descent.

Slate grey nevi typically appear on the buttocks, upper legs and lower back. The smooth and flat spots can look similar to bruises, but are painless to the touch. They can be approximately two to eight centimeters wide with an irregular shape without defined edges. These spots may occur with other vascular birthmarks and diseases that affect metabolism. The rare metabolic conditions associated with slate grey nevi include Hunter’s syndrome, Hurler’s disease, Niemann-Pick disease, mannosidosis and Mucolipidosis.

Slate Grey Nevi Treatment

Slate grey nevi is harmless and poses no risk of cancer or other serious long-term health conditions. It can be important for a doctor to examine your child early for these marks and document them in your child’s medical records. This is because slate grey nevi look similar to bruises and may raise concerns of child abuse by other unsuspecting adults. You may want to take photographs at birth to help explain the condition to others who may raise concerns. An accurate diagnosis by a board-certified dermatologist is also necessary because it may be mistaken for other health conditions.

Treatment is not necessary unless these marks appear with another medical condition. Adults with slate grey nevi may wish to have laser surgery to remove the marks. Spots that change color and shape may be a sign of another medical condition that may need immediate treatment. If you notice any changes, take your child to a dermatologist for an examination. Medical treatment may also be necessary for teens if the spots become a visible source of embarrassment.

Schedule a Consultation

Slate grey nevi generally pose no health risks except in rare cases where other medical conditions may be involved. You may want to have your child’s condition monitored by an expert medical professional to ensure no problems develop. At Vascular Birthmark Institute, our doctors have over 30 years of experience with vascular birthmarks like slate grey nevi. We can examine your child and help you explore treatment options if necessary. Contact us today to schedule a consultation.

Posted on behalf of Vascular Birthmark Institute

210 East 64th Street, 3rd Floor
New York City, NY 10065

Phone: (212) 434-4050

FAX: (212) 434-4059


Monday-Friday: 8:30am-5pm