Birthmarks are marks on the skin that a baby can develop before birth or soon after. Birthmarks can be flat or raised, have regular or irregular borders, and have different shades of coloring from brown, tan, black, or pale blue to pink, red, or purple.
What Causes Birthmarks?
Doctors don’t know what causes most birthmarks. They can’t be prevented and they’re not caused by anything done or not done during pregnancy. Most aren’t related to trauma to the skin during childbirth. Some kinds may run in families, but a genetic cause hasn’t been found.
What Are the Types of Birthmarks?
There are two main types of birthmarks, which have different causes:
Vascular Birthmarks
The most common vascular (blood vessel) birthmarks are macular stains, hemangiomas, and port-wine stains:
- Macular stains. Also called salmon patches, angel kisses, or stork bites, these faint red marks are the most common type of vascular birthmark. Macular (MA-kyuh-ler) stains typically are on the forehead or eyelids; the back of the neck; or on the nose, upper lip, or back of the head. They may be more noticeable when the baby cries. Most often they fade on their own by the time a child is 1 to 2 years old, although some last into adulthood.
- Hemangiomas. Hemangiomas are superficial when they’re on the surface of the skin (“strawberry marks”), deep when found below the skin’s surface, and compound when they affect both layers. A hemangioma (hee-man-jee-OH-muh) can be slightly raised and bright red, and usually won’t be visible until a few days or weeks after a baby is born. Deep hemangiomas might look bluish because they involve blood vessels in deeper layers of the skin.
Pigmented Birthmarks
The most common pigmented birthmarks are café-au-lait spots, Mongolian spots, and moles:
- Café-au-lait spots. These very common spots are the color of coffee with milk, which explains the name. They can be anywhere on the body and sometimes increase in number as a child gets older. One alone is not a problem. But call your doctor if your child has 6 or more spots that are larger than a pencil eraser (for a younger child), or larger than a dime (for an older child). Having many café-au-lait spots can be a sign of neurofibromatosis (a genetic disorder that causes abnormal cell growth of nerve tissues).
- Mongolian spots. These flat, bluish-gray patches are often found on the lower back or buttocks. They are most common on darker skin, such as on children of Asian, American Indian, African, Hispanic, and Southern European descent. They usually fade — often completely — by school age without treatment.
How Are Birthmarks Treated?
Macular stains usually fade away on their own. Ones at the back of the neck may last longer, but are not very noticeable. Most other vascular birthmarks can be treated.
Port-wine stains and some hemangiomas can be disfiguring and upsetting for children. Small hemangiomas in less visible locations usually don’t need treatment, as most shrink back into themselves by the time a child is 10. Doctors can treat larger or more visible hemangiomas with medicine put directly into the hemangioma, given into a vein (with an IV), or taken by mouth (oral).
When Should I Call the Doctor?
A doctor should check a birthmark when it first appears to see what type it is, and to decide what monitoring or treatment it needs, if any.
Call the doctor if a birthmark ever bleeds, hurts, itches, or gets infected. Like any injury where there is bleeding, clean the wound with soap and water and, using a gauze bandage, place firm pressure on the area until the bleeding stops. If the bleeding doesn’t stop, call the doctor.
What Else Should I Know?
It can be a shock at first to see a birthmark on your newborn. If the birthmark is clearly visible, people might ask questions or stare, which can feel rude. It helps to have a simple explanation ready to handle this. Most people mean no harm, but it’s also OK to let them know if they’ve gone too far.
Even at a young age, kids watch how their parents respond to such situations. This is where they learn how to cope with others’ reactions. Talking simply and openly about a birthmark with kids makes them more likely to accept one as just another part of themselves, like hair color. Practice simple answers they can use if asked about it, like “It’s just a birthmark. I was born with it.” It’s also helps kids emotionally to be around supportive family and friends who treat them normally.