Birthmarks in Babies and Children: Types, Causes, and When to Worry

Many newborns and children have one or more birthmarks, and most are completely harmless. Parents often worry when they first see a new mark on their baby’s skin, but in many cases, these spots fade with time or simply become part of the child’s normal appearance.

This guide explains the main kinds of birthmarks, why they appear, how they usually change, and when it is important to seek medical advice or treatment.

What Are Birthmarks?

A birthmark is an area of skin that looks different from the surrounding skin because of its color, texture, or raised appearance. These marks may be present at birth or show up in the first weeks of life.

Doctors generally group birthmarks into two broad categories:

• Vascular birthmarks – caused by extra or unusually formed blood vessels in or under the skin.
• Pigmented birthmarks – caused by extra color-producing cells (melanocytes) that create patches of darker or differently colored skin.

Some experts also describe a third group that includes other, less common skin growths or developmental skin differences that appear at birth.

Why Do Birthmarks Happen?

The exact reasons some babies develop birthmarks are not always known. In most cases, they are not caused by anything a parent did or did not do during pregnancy.

Current medical understanding suggests:

• Vascular birthmarks come from blood vessels that formed or grew in an unusual way before birth.
• Pigmented birthmarks occur when pigment-making cells cluster together or are more active in one area than in the surrounding skin.

Only a small number of birthmarks are linked to genetic conditions or syndromes. When that happens, the pattern, number, and location of marks usually give doctors clues that more testing is needed.

Main Types of Birthmarks

The table below summarizes the two main groups of birthmarks and gives examples parents may hear about.

Common Vascular Birthmarks

1. Salmon Patches (Often Called “Stork Bites” or “Angel Kisses”)

Salmon patches are among the most frequent birthmarks seen in newborns. They are flat, pink to light red areas that become more noticeable when a baby cries or when the skin is warm.

Typical features include:

• Location on the eyelids, between the eyebrows, upper lip, or back of the neck.
• Soft, flat, and not scaly or bumpy.
• Often fade within the first few years of life, especially those on the face.

Salmon patches do not usually need treatment and rarely cause medical problems.

2. Infantile Hemangiomas

Infantile hemangiomas are raised or deep clusters of extra blood vessels that appear shortly after birth. They are one of the most common tumors of infancy, although they are benign (non-cancerous).

Important points for parents:

• They may not be visible at birth but usually appear in the first weeks of life.
• They tend to grow quickly during the first 3–6 months, then stop enlarging and slowly shrink over several years.
• By around age 10, most hemangiomas have faded considerably, though a small mark or loose skin may remain.

Medical care is especially important if a hemangioma:

• Is near the eyes, nose, mouth, or airway (can affect vision, breathing, or feeding).
• Ulcerates (develops an open sore), bleeds, or becomes painful.
• Is very large, multiple, or located over the lower spine or liver, which can rarely be linked with internal issues.

Modern treatments such as beta-blocker medicines (for example, oral propranolol) or laser therapy can help control growth and improve appearance when needed.

3. Port-Wine Stains

Port-wine stains are flat birthmarks caused by permanently widened tiny blood vessels (capillaries) in the skin.

They have several key characteristics:

• Present at birth and usually located on the face, neck, or upper body.
• Color ranges from light pink to deep red or purple.
• Grow as the child grows; they do not fade on their own.
• Skin over the mark may become thicker or more uneven (cobblestoned) in adulthood.

Some port-wine stains are more than a cosmetic issue. When they appear on certain areas of the face, they can be associated with rare conditions that affect the brain, eyes, or blood vessels, such as Sturge–Weber syndrome or Klippel–Trénaunay syndrome.

Children with large or facial port-wine stains should usually be evaluated by a pediatric dermatologist. Pulsed dye laser treatment is often used to lighten the marks and reduce thickening over time.

Common Pigmented Birthmarks

1. Café-au-Lait Spots

Café-au-lait spots are flat, light to medium brown patches that may be present at birth or appear in early childhood.

Typical features:

• Oval or irregular shape with well-defined edges.
• Color similar to “coffee with milk,” which is where the name comes from.
• Can be single or multiple; spots may get bigger as the child grows.

One or two café-au-lait spots are quite common and usually harmless. However, having many such spots, or very large ones, can sometimes be a clue to an underlying genetic condition such as neurofibromatosis type 1, especially if other signs (like small bumps on the skin or learning difficulties) appear.

2. Congenital Melanocytic Nevi (Moles Present at Birth)

Congenital melanocytic nevi are moles that are already present when a baby is born. They are made up of benign clusters of pigment cells called melanocytes.

These birthmarks vary widely:

• Size can range from small dots to large patches covering a big part of the body.
• Color may be tan, brown, or nearly black.
• Surface may be flat, slightly raised, or bumpy; hair can grow from the mole.

Doctors usually classify these nevi based on their expected adult size (for example, small, medium, or large/giant). The risk of melanoma (a serious form of skin cancer) is generally higher for very large congenital nevi than for small ones, although the overall risk remains low in childhood.

Because of this, regular skin checks and photos to track changes over time are often recommended. Sometimes surgery is considered to remove part or all of a large mole, depending on its size, location, and appearance.

3. Dermal Melanocytosis (Formerly Called Mongolian Spots)

Dermal melanocytosis are flat blue-gray patches that usually appear on the lower back or buttocks of infants.

Key details include:

• They are more common in babies with darker skin tones, including many Black, Asian, Native American, and Hispanic infants.
• Color can range from slate gray to blue-black.
• They often fade or disappear completely by early childhood.

Dermal melanocytosis does not turn into cancer and does not require treatment. Because the patches can look like bruises, it is important for healthcare providers to document them to avoid confusion later.

Other Less Common Birthmarks

A few other birthmark types come from different kinds of skin cells or structures and may have their own specific concerns.

Epidermal and Sebaceous Nevi

Epidermal nevi are overgrowths of the top layer of skin, while sebaceous nevi arise from oil (sebaceous) glands in the skin.

• They are often present at birth and may appear as yellow, tan, or orange plaques, sometimes on the scalp or face.
• Hair may be absent in the area of a sebaceous nevus.
• These marks usually do not fade as a child grows.

Very rarely, certain types of skin cancer can develop within some of these nevi later in life, so dermatologists may recommend monitoring and, in some cases, surgical removal.

Do Birthmarks Need Treatment?

Most birthmarks do not require medical treatment. Care decisions usually depend on:

• Whether the birthmark affects a vital function (like sight, breathing, or feeding).
• Risk of complications, such as ulceration, bleeding, or rare associated syndromes.
• Potential for emotional impact due to size or location (for example, prominent marks on the face).
• Any small risk of future skin cancer in certain pigmented lesions.

Possible treatment options include:

• Watchful waiting and regular checkups – very common when marks are expected to fade or stay stable.
• Topical or oral medicines – such as beta-blockers for some problematic hemangiomas.
• Laser therapy – often used to lighten port-wine stains or other vascular marks.
• Surgery – occasionally recommended for certain large moles, sebaceous nevi, or deforming lesions.

Your child’s pediatrician may refer you to a pediatric dermatologist or a specialized birthmark clinic to decide which approach is best.

When Should Parents Call the Doctor?

Some birthmarks are best evaluated promptly, while others can wait for a routine checkup. Contact your child’s healthcare provider if you notice:

• A birthmark that grows extremely quickly, bleeds, forms open sores, or seems painful.
• A mark near the eye, nose, lips, or airway, or one that seems to interfere with movement or feeding.
• Multiple café-au-lait spots or very large pigmented patches.
• Any change in a mole’s color, border, texture, or size that seems unusual.
• A large port-wine stain on the face, especially around the eye or forehead.

In emergencies, such as heavy bleeding, difficulty breathing, or sudden weakness or seizures in a child with certain vascular birthmarks, seek urgent medical care.

Emotional and Social Aspects

Even when a birthmark is medically harmless, it may still draw unwanted attention or questions as a child grows. Parents can support their child by:

• Using simple, honest language to explain what the mark is (“a special mark you were born with”).
• Modeling confidence and avoiding negative comments about appearance.
• Preparing older children with brief responses to questions from peers (“It’s just a birthmark, it doesn’t hurt.”).
• Talking with a pediatrician if teasing or self-consciousness becomes a significant concern; counseling or support groups can sometimes help.

Frequently Asked Questions (FAQs)

Are most birthmarks harmless?

Yes. The majority of birthmarks in babies and children are medically harmless and never cause health problems. Many either fade with time or remain stable without affecting growth or development.

Can birthmarks be prevented?

There is no known way to prevent common birthmarks. They generally happen during early development of the skin and blood vessels and are not related to anything a parent does during pregnancy.

Do birthmarks always appear at birth?

No. Some are visible right away, while others (such as many infantile hemangiomas) appear days or weeks after birth and then go through a growth phase before slowly shrinking.

Can birthmarks turn into skin cancer?

Most birthmarks never become cancerous. However, certain large or complex pigmented birthmarks, such as very large congenital melanocytic nevi, have a higher lifetime risk of melanoma than normal skin. Doctors usually recommend regular monitoring for these children and may sometimes advise surgery.

Should my child avoid the sun because of a birthmark?

All children, regardless of birthmarks, benefit from sun protection to reduce skin damage. For pigmented lesions and large moles, good sun habits (shade, clothing, and sunscreen when appropriate) are especially important, since sunburn can injure the skin and complicate monitoring. Ask your pediatrician about age-appropriate sun safety for infants and children.

Who can help evaluate my child’s birthmark?

Your first stop is usually your child’s pediatrician or family doctor. For more complex or unusual marks, they may refer you to a pediatric dermatologist, an ophthalmologist (for eye-related issues), or a specialized birthmark or vascular anomalies clinic.