Birthmarks are coloured marks that are visible on the skin. Most of them are either:
- pigmented birthmarks (usually brown), caused by clusters of pigment cells, or
- vascular birthmarks (often red, pink or purple), caused by abnormal blood vessels in or under the skin.
This article focuses on vascular birthmarks. See the Health A-Z topic about pigmented birthmarks for information about café-au-lait spots (coffee-coloured spots), Mongolian spots and congenital melanocytic naevi (moles present at birth).
About vascular birthmarks
Most experts classify vascular birthmarks as either:
- haemangiomas, which are the most common type, and include strawberry marks, or
- vascular malformations, which include port wine stains.
Vascular birthmarks are caused by a problem with blood vessels in or under the skin. Most birthmarks appear at birth or shortly after.
They can vary in colour: if the affected vessels are deep, the birthmark will appear blue. If surface vessels are affected, it will appear red, purple or pink. Vascular birthmarks can also be flat or raised (see Birthmarks - symptoms for more information).
Vascular birthmarks usually occur in the head and neck area, mainly on the face. However, they can appear anywhere, including inside the body.
A haemangioma is a raised (usually red) mark on the skin. A common example is the strawberry mark.
Most haemangiomas are initially small and flat, and you cannot tell if they will become large or problematic later on.
A typical haemangioma grows rapidly for the first four or five months, then grows slowly for up to a year (although some differ from this pattern). Over the following years it will fade. Most eventually go away, although some (particularly large ones) may leave the skin stretched or deformed.
Very bulky haemangiomas may be surgically removed or treated with drugs (see Birthmarks - treatment for more information).
Vascular malformations may be made up of very small blood vessels, veins, or a mixture of arteries and veins.
Some vascular malformations are present at birth, but others may not appear until later in infancy or childhood.
Two common vascular malformations are the:
- salmon patch (also called stork mark), and
- port wine stain.
Salmon patches often disappear on their own a few months after birth.
Port wine stains tend to be sensitive to hormones and may become more noticeable around puberty, pregnancy and the menopause. Most are permanent and may deepen in colour over time.
Laser treatment can fade the mark but will not get rid of it completely. The fading is not permanent.
Nine out of 10 haemangiomas will disappear by the time your child is nine years old. However, a minority of children will have a more troublesome haemangioma that requires the help of a specialist. Rarely, haemangiomas may block the airway, affect vision, or become ulcerated.
Port wine stains do not get better without treatment.
- Most common vascular birthmark (especially the strawberry mark).
- Present at birth, or appears shortly after.
- Red, blue or purple raised mark on the skin.
- Often develops on the head or neck.
- More common in girls.
Port wine stains
- Red or purple flat mark on the skin.
- Often occurs on one side of the face.
- About three in 1,000 newborn babies affected.
- Does not get better without treatment.
- Flat, pink area often occuring on the mid-forehead, above the eyes or on the back of the neck.
- Often disappears a few months after birth.
- Extremely common.
A haemangioma is a collection of tiny blood vessels that produces a raised mark on the skin.
It may be present at birth or appear shortly after. It often develops on the head or neck, but can occur anywhere on the body, including internal organs.
Most haemangiomas start out small and flat. You cannot tell if they will become large or problematic later on.
Usually there is just one haemangioma, but some babies have several.
There are three main types of haemangioma:
- A superficial haemangioma (strawberry mark) is red and appears on the surface of the skin.
- A deep haemangioma is usually blue or purple in colour, and occurs deeper in the skin.
- A mixed haemangioma has both superficial and deep parts.
How they develop
A haemangioma may start as a small area of pink skin, which turns into a coloured (usually red) spot.
A typical haemangioma will grow rapidly for the first four or five months, then grow slowly for up to one year (although some will differ from this pattern).
Over the following years it will start to fade (known as regression). According to the British Association of Dermatologists:
- 30% will have faded by the child's third birthday,
- 50% by the child's fifth birthday, and
- 70% by the child's seventh birthday.
Larger haemangiomas may leave the skin deformed or stretched.
Port wine stains
A port wine stain is a flat mark on the skin that can range in colour from pale pink to dark purple. It is always present at birth.
It can vary in size, from a few millimetres to several centimetres in diameter, and often occurs on one side of the face. It is also common on the upper body.
Port wine stains never truly go away. Laser treatment can fade the mark, but this is only temporary, so you will need to have laser treatment throughout your life to keep it faded (see Treatment for more information).
Without laser treatment, a port wine stain may darken and grow larger with age. It may develop ridges or raised bumps. It tends to be sensitive to hormones, and becomes more noticeable around puberty, pregnancy and the menopause.
If it is present around the eyelids, it may lead to increased pressure within the eye (see Complications for more information).
Salmon patches (also called stork marks) are flat, pale pink areas that often occur between the eyebrows, on the middle of the forehead, on the upper eyelids, or on the back of the neck.
Many of them fade quickly and usually disappear within a few months after birth. However, salmon patches on the forehead may take up to four years to disappear. Patches on the back of the neck often persist.
The cause of vascular birthmarks is not fully understood. Birthmarks are not usually inherited.
Haemangiomas are caused by an overgrowth of tiny blood vessels under the skin, although it is not understood exactly why this happens.
Port wine stains
Port wine stains are caused by a problem with the tiny blood vessels, known as capillaries, in the area where the mark forms.
Normally, capillaries can narrow (constrict) or widen (dilate). Dilated vessels cause more blood to flow to the skin to allow the blood to cool when you are hot. Constricted vessels prevent too much blood reaching the surface of the skin when you are cold.
In the case of port wine stains, the capillaries remain dilated. This results means that blood is constantly supplied to the skin in that area, which makes it permanently red or purple in colour.
It is thought that port wine stains occur because the nerves that control the widening or narrowing of the capillaries do not function properly, or there are not enough of them.
Port wine stains are sometimes related to other conditions, such as Sturge-Weber syndrome and Klippel-Trenaunay syndrome (see Complications for more information).
Salmon patches (stork marks) are caused by a collection of tiny blood vessels under the skin. They are sometimes more noticeable when a baby cries.
- Blood vessels
- Blood vessels are the tubes in which blood travels to and from parts of the body. The three main types of blood vessels are veins, arteries and capillaries.
- Congenital means a condition that is present at birth. The condition could be hereditary or develops during pregnancy.
- Blood supplies oxygen to the body and removes carbon dioxide. It is pumped around the body by the heart.
While the vast majority of haemangiomas automatically shrink after a year, some may leave the skin deformed or stretched. In these cases, plastic surgery may be an option to improve the appearance of the distorted skin. For more information, go to Health A-Z: plastic surgery.
If the haemangioma is complicated or large, you may be offered medication. This is usually the beta-blocker propranolol (see Health A-Z: beta-blockers). If your haemangioma has formed an ulcer, you may be offered surgery or laser treatment (see below).
Complicated or large haemangiomas
Some haemangiomas may cause complications that will need treatment.
A haemangioma near your child's eye, nose or mouth may cause problems with vision, breathing and feeding. Haemangiomas on the lip or around the nappy area are more likely to form ulcers, which sometimes bleed and can be painful.
The exact method of treatment will depend on the severity and location of the haemangioma. For example, if the haemangioma affects your child's vision, they will usually need to take propranolol, in liquid form. This will shrink the birthmark.
If your child has breathing difficulties because of a haemangioma in the airway, they may need to have laser treatment during a microlaryngoscopy and bronchoscopy (a test that allows the doctor to look into your child's airway using a small telescope, known as an endoscope). They may also be given propranolol.
Your child may need to have a tracheostomy (artifical opening into the windpipe) to improve their breathing.
Monitoring internal haemangiomas
If a haemangioma is present in your child's internal organs, they may need to have an ultrasound scan or magnetic resonance imaging (MRI) scan. An MRI scan uses a strong magnetic field and radiowaves to produce detailed pictures of the inside of your body.
Port wine stains
Port wine stains are permanent. The treatment options are:
- pulsed dye laser treatement, which can fade the mark, and
- camouflage make-up, which can disguise it.
Infants with port wine stains should be offered pulsed dye laser treatment early on, because the vessels are thinner at this stage and respond better to the treatment.
Pulsed dye laser treatment
Pulsed dye laser treatment lightens the affected area of skin, and it is the best treatment for a port wine stain.
The laser passes through a fibre optic cable. On the end of the cable is a device that looks like a pen. This is held gently against the surface of your child's skin, and a button is pressed, which sends a shot of light to the skin.
The light goes less than 1mm into the skin. It is absorbed by the blood vessel just beneath the surface, which causes it to heat up. The heat damages the blood vessel, which creates a bruise, but this will fade within a week or two.
During and/or after treatment, your child's skin is cooled to reduce discomfort. A jet of cold air is blown onto the skin during treatment.
A local anaesthetic (to numb the area around the skin), such as an anaesthetic cream, is used in older children. A general anaesthetic (where you are put to sleep) is used for younger children.
The side effects of laser treatment are minimal.
Up to 10 treatment sessions may be needed at intervals of three to four months.
The treatment's effectiveness will depend on how prominent and dark the affected area is.
- If the birthmark is superficial (shallow), the mark may be hardly noticeable after treatment.
- If the birthmark is dark to begin with, the mark may still be visible after several treatments.
Port wine stains tend to come back after laser therapy is completed (after two to four years), therefore further treatment will be needed.
You can get a prescription for a special type of camouflage make-up, which will cover up the birthmark.
The Irish Red Cross has specialist skin camouflage clinics around the country.
Salmon patches (stork marks) are blemishes that often disappear a few months after birth, so they do not need to be treated.
- Body tissue is made up of groups of cells that perform a specific job, such as protecting the body against infection, producing movement or storing fat.
- Immune system
- The immune system is the body's defence system, which helps to protect it from disease, bacteria and viruses.
- Malignant is a term used to describe a life-threatening or worsening condition. In the case of tumours, malignant means cancerous.
- A biopsy is a test that involves taking a small sample of tissue from the body so it can be examined.
- Congenital means a condition that is present at birth. The condition could be hereditary or develop during pregnancy.
Some haemangiomas can be life-threatening or cause severe problems. They may interfere with eating, breathing or eyesight, so they need to be Treatment treated (see for more information).
If your child has a haemangioma near their eye, nose, mouth or nappy area, they may need to be referred to a specialist.
Some haemangiomas may bleed or become infected. If the birthmark bleeds, apply pressure to it until the bleeding stops.
See your doctor if your child's haemangioma forms an ulcer, because it can become infected and may be very painful. Keep the wound clean and covered with a dressing. It should heal within two weeks.
If your child has more than five haemangiomas, they may also have internal haemangiomas. It is very unusual for these to cause any problems, but an ultrasound may be carried out to see if any haemangiomas are present.
Most internal haemangiomas cause no symptoms. Very rarely, they might cause:
- coughing and difficulty breathing, which may indicate airway haemangiomas, or
- blood in the stools, which may indicate haemangiomas in the bowel.
Port wine stains
If you have a port wine stain, you may have any of the following complications:
- Glaucoma (raised pressure within the eye, which affects vision). You may have this condition if the birthmark is around your eye.
- Sturge-Weber syndrome. This is a rare disorder that affects the eyes and brain. It is usually associated with a large port wine stain, which extends onto your forehead or scalp.
- Soft tissue hypertrophy (the tissue beneath the birthmark enlarging). This may occur on a lip, for example.
- Klippel-Trenaunay syndrome. This is a rare disorder present at birth, where the blood vessels fail to form properly. If your child has a port wine stain on their limb, and this is enlarged, they may have Klippel-Trenaunay syndrome.
If you have any of these associated conditions, you will need to be treated by a specialist.