What is a birthmark?

A birthmark is a congenital issue on the skin that is present at birth. Birthmarks can appear on any area of the body or face and vary in size, shape and appearance. As you age, birthmarks can change in size, color and shape.

Causes of a birthmark

The exact cause of a birthmark is unknown, but most dermatologists agree that they are not inherited from the mother’s or father’s genes.

There are theories on what causes different types of birthmarks:

  • Strawberry marks may be caused by an accumulation of cells in the lining of a baby’s blood vessels
  • A small piece of placenta that lodged inside the developing embryo early during a pregnancy
  • Port wine stains can be caused by dilation or constriction of capillaries
  • Salmon patches can be caused by accumulation of capillaries under the skin
  • Proteins in the placenta during pregnancy can be linked to birthmarks

Risk factors for a birthmark

Although most birthmarks do not cause long-term health issues, some birthmarks can lead to complications later.

Risk factors include:

  • Birthmarks that develop into open sores or ulcers that can be painful and infected.
  • Birthmarks that develop into a malignant cancer
  • Children with port wine stain birthmarks around the eye are more likely to develop glaucoma later in life
  • Patients with a large port wine stain birthmark on the forehead or scalp are more likely to develop Sturge-Weber syndrome — a neurological disorder.

Symptoms of a birthmark

Symptoms of birthmarks vary depending on the type of birthmark you have. There are a variety of types of birthmarks including:

Pigmented birthmarks:

  • Café-au-lait spots
    Cafe-au-lait birthmarks are light brown spots that look like coffee with milk. Some cafe-au-lait spots are present at birth, while others appear after a child is born. They form when the skin produces excess pigment. Although most cafe-au-lait spots are harmless, if you have more than six cafe-au-lait spots, they could be associated with neurofibromatosis type 1.
  • Dermal melanocytosis
    Dermal melanocytosis, also known as Mongolian spots, are flat blue-gray patches that appear on the lower back and buttocks. Dermal melanocytosis are typically present at birth and frequently fade during a child’s early life. They do not typically require treatment.
  • Congenital nevi (moles)
    Congenital nevi are moles that are present when you are born. These moles are often larger, may have hair growing from them and can appear anywhere on the body. They range from light brown to black and can feel bumpy or flat. Although most moles present at birth are harmless, your dermatologist should examine all moles to rule out more serious conditions.
  • Sebaceous nevi
    Sebaceous nevi are a type of birthmark that is present at birth and generally located on the scalp. This type of birthmark forms from an overgrowth of the sebaceous glands, glands secrete a substance that moisturizes the skin and hair. Sebaceous nevi are orange or tan in color and generally are a long, oval shape. Although it is rare for sebaceous nevi to become cancerous, you should have them checked regularly. Your doctor may recommend surgical removal of a sebaceous nevi, if he or she suspects it may turn cancerous.

Vascular birthmarks:

  • Strawberry hemangiomas
    Strawberry hemangiomas are bright red and appear on the skin’s surface. They can either be flat and splotchy or be a raised, hard bump.
  • Deep hemangiomas
    Deep hemangiomas typically do not show on the surface of the skin until a few weeks or months after birth. They form deep in the skin and are characterized by blue-gray bumps.
  • Salmon patches
    Salmon patches are small, flat and pink/red marks that can appear on any area of the body. They typically are harmless and formed from clusters of blood vessels. Salmon patches rarely require treatment.
  • Venous vascular malformations
    Venous vascular malformations are red or purple birthmarks that occur when groups of veins become enlarged. Venous vascular malformations may appear at birth or appear as a child ages.
  • Port wine stains
    Port wine stains are flat pink or red areas typically found on the face that may darken or grow as a child ages. They are typically present at birth. In rare cases, they are associated with a medical condition called Sturge-Weber syndrome.

Diagnosis of birthmarks

Your doctor can typically diagnose a birthmark during a physical exam. If your doctor suspects you have another condition, he or she may recommend further testing such as:

  • Ultrasound
    If your doctor suspects another medical condition associated with a birthmark, he or she may order an ultrasound. The ultrasound can show how deep the birthmark is and whether it impacts other body parts or organs.
  • MRI
    If an ultrasound does not provide enough information, your doctor may order an MRI. An MRI scan allows your doctor to see the extent of a certain birthmark.
  • Biopsy
    A biopsy may be necessary if a mole that was present at birth looks suspicious. During a biopsy, your doctor will remove a sample of tissue and send to a laboratory for evaluation.

Treatments for birthmarks

Although most birthmarks do not cause issues and fade away without treatment, if your birthmark is causing health issues, your doctor may recommend you get it treated.

Treatment for birthmarks may include:

  • Corticosteroids
    A corticosteroid injection directly into the birthmark or taken via a pill can shrink or stop a birthmark from growing.
  • Interferon alfa-12
    Interferon alfa-12 is an alternate treatment if a corticosteroid is not effective. It also works by shrinking or stopping the birthmark from growing.
  • Laser therapy
    Laser therapy is most commonly used for port wine stains and birthmarks that are close to the surface of the skin. It is most successful when laser therapy is started during the infancy stage. Typically, it takes a few treatments to be effective.
  • Surgery
    Surgery is only used as a last resort option to treat birthmarks when all other treatments have failed. People with deep hemangiomas or large moles may be candidates for surgical removal of a birthmark. Surgery is generally performed in an outpatient clinic or your doctor’s office. Your doctor will use a small scalpel to remove the birthmark or remove a large birthmark over the course of a few visits.

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