What are birthmarks?

Birthmarks are areas of discolored or raised skin that are seen at birth or within a few weeks of birth. Birthmarks may be made up of malformed pigment cells or blood vessels.

Medical experts don’t know what causes birthmarks. But most of them are not cancer (benign) and don't require treatment. Babies with birthmarks should be checked and diagnosed by a healthcare provider.

What are the most common types of vascular birthmarks?

These are the most common types of vascular birthmarks:

• Macular stains or salmon patches. These are characterized by pink to red marks that may appear anywhere on the body. Angel kisses and stork bites are the most common type of vascular birthmark:

  • Angel's kisses. Marks located on the forehead, nose, upper lip, and eyelids that usually disappear with age.

  • Stork bites. Marks on the back of the neck that may disappear with age.

• Hemangioma. These are a common vascular birthmark. Hemangiomas become visible within the first few weeks or months of life and continue to grow rapidly for about 6 to 9 months. Then they slowly lose this red color and shrink. They are called strawberry patch hemangiomas. By age 5, 50% of these go away and 90% go away by age 9 without any treatment. Hemangiomas that grow into other organs or structures or become ulcerated should be checked by your healthcare provider.

• Port-wine stain. A port-wine stain is a flat, pink, red, or purple mark that appears at birth, often on the face, arms, and legs. It continues to grow as the child grows. Port-wine stains don't go away, and may become more purple or thicker with age. These birthmarks often need treatment if located on the eyelid or forehead. Port-wine stains involving the face may cause eye problems and be linked with other developmental disorders.

What are the most common types of pigmented birthmarks?

These are the most common types of pigmented birthmarks:

• Moles. These can be skin-colored, brown or black, flat or raised, and small or large. They can happen anywhere on the body. Moles can also happen in adulthood. But only moles that are present at birth are considered birthmarks. Other moles can appear within the first 2 years of life. Moles can develop into cancer later in life. Larger moles have a higher risk of becoming cancerous.

• Cafe-au-lait spots. This is French for coffee with milk. These are usually oval-shaped and light brown. Typically these fade with age and are not a problem. But many of them grouped together can be a sign of other health issues and should be checked by a healthcare provider. 

• Mongolian spots. These are blue or blue-gray spots on the lower back or buttocks. They are most common in babies with darker skin, such as African-American or Asian babies. They can be mistaken for bruises. They usually fade with age.