Birthmarks

Any mark that is present on the skin at birth, or that develops soon afterwards, is called a birthmark. They are very common – most children have a mark of some sort. Most are harmless and some go away as the child grows. Occasionally, a birthmark may be a sign of other problems or diseases. Check with your doctor if you are not sure, especially if the mark changes unexpectedly.

The cause is unknown
No one knows why some children have birthmarks and others do not. They are certainly not caused by such things as the mother seeing something strange or having a fright during pregnancy, as has been suggested by some. The tendency to have birthmarks may be inherited; some marks may be similar to marks on other family members, but most are not. Some are caused by an overgrowth of fine blood vessels or of pigment (colour) cells.

Different types of birthmarks
There are various different types of birthmarks including:

• ‘Stork bite’ mark
• Mongolian blue spots
• Strawberry mark
• Café au lait spots
• Congenital melanocytic naevus.

• Pink, flat and irregular shaped marks.
• The skin is not thickened and you cannot feel any difference when you touch the mark.
• They are usually on the back of the neck, eyelids, forehead and, sometimes, on the top lip.
• Nearly half of all babies have a ‘stork bite’ mark.
• The marks usually disappear by 12 months of age, if not earlier.
• The mark at the back of the neck may stay for longer, but it is usually covered by hair and out of sight.

• Bluish, irregular flat patches.
• They are mainly found on the back and bottom, although any area can be affected.
• There is no thickening or change to the feel of the skin.
• They are more common in babies from ethnic groups that have darker skin colouring, such as those with black hair and olive or darker skin.
• They are harmless and become less obvious as the child grows.
• They can be confused with bruises.

• Red, raised and lumpy areas.
• They usually appear at around one to four weeks of age, then get bigger – sometimes quite quickly – for a few months.
• They stop growing between six and 12 months of age, then gradually disappear over the next few years.
• The skin of the birthmark is as strong as any other skin. It might rarely bleed if knocked hard or scratched, or develop an ulcer on the surface and need to be treated.
• Sometimes the strawberry mark may grow on the face, near the eye. If it blocks vision it is usually treated so that the child develops good binocular vision. It will still go away if untreated.

• Flat, roughly oval-shaped light brown (milk coffee coloured) spots.
• May be present at birth or appear in early childhood.
• Many children have one or two of these – they are not signs of a health problem.

• Small moles and freckles.
• May be seen on babies, but more often they develop in childhood.
• Some are large dark brown, blue or black birthmarks that sometimes grow dark hairs.
• Some are raised and lumpy, while others are flat and irregular in shape.

• Flat, large areas of skin that are darker (pink or purplish colour) than the skin around them.
• They are usually present from birth and the colour gets darker (from pale pink to deep red-purple) as the child grows.
• They may thicken and become lumpier.
• The marks are often on the face, sometimes just on one side. They may have a clear edge along the middle of the face, but they can appear anywhere on the body.

• Strawberry mark – sometimes a strawberry birthmark will grow over an eye or may block one side of the nose. In these cases, they can be treated – often with laser treatment.
• Congenital melanocytic naevus – sometimes these will need to be removed because they may be a cancer risk or because the child finds the mark distressing. Others that start to grow, often during the teenage years, need to be carefully watched. If the mark changes, get it checked by your doctor.
• Port wine stain birthmarks – these don’t go away by themselves. It is best to have expert advice about treatment early, because their appearance can affect a child’s feelings about themselves. Laser therapy usually gives good results.

• Sturge-Weber syndrome – symptoms include a port wine stain birthmark on the upper eyelid and forehead, and abnormalities of the brain (and sometimes of an eye).
• Klippel-Trenaunay-Weber syndrome – symptoms include a port wine stain birthmark on the leg (usually). The bones, muscles and other tissue near the birthmark grow larger than the other normal limb.

• Your doctor
• Paediatrician
• Dermatologist.

• Any mark that is present on the skin at birth, or that develops soon afterwards, is called a birthmark.
• Birthmarks are very common – most children have a mark of some sort.
• Occasionally, a birthmark may be a sign of other problems or diseases.

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