Mole (Congenital nevus)

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More than 200,000 US cases per year

  • Often self-diagnosable
  • Symptoms: Flat or raised small skin marks
  • Color: Typically dark brown or black
  • Location: Anywhere on the skin
  • Treatment: No treatment necessary; diathermy

Moles are brown, round, raised and sometimes hairy birthmarks that usually do not disappear by themselves over time. They are usually harmless but it is important to keep track of the changes. They can be removed if they are bothersome, unsightly or if they start to change shape, size or color.

Symptoms of Moles

All adults have moles. The first are beginning to appear in the first few years of life, and then more and more until about 30 years old. Women have more birthmarks when they are pregnant. It is not uncommon to have about 70 spots or more. Moles contain extra pigment which is the coloring agent makes skin darkening when exposed to sunlight. They can have many different looks and different in size, shape and color. Moles are sometimes called liver spots and the medical language called the nevus.

What can I do?

You should keep track of the changes in moles and avoid burning up in the sun. Use sunscreen with sufficient sun protection factor depending on where you are.

Should I seek medical care?

Almost all moles are harmless, but a few may develop into cancer. It rarely happens in children and adolescents under 18 years old.

Your mole should be examined more closely by a doctor if it:

  • Turns into a wound
  • Grows or changes shape
  • Changes color or becomes mottled
  • Begins to itch or bleed
  • Is located where the collar or waistband rubs against it

Treatment for Moles

A mole usually needs to be investigated further to be surgically removed with a local anesthetic. Within general health care, birthmarks can only be removed if there is a medical reason to do so.

Pigmented skin lesions that are surgically removed should be examined in the laboratory. You should not get moles removed by scraping, laser or freezing. Moles should not be removed with the so-called diathermy, where the tissue is burned with the help of electricity, since it is not possible to examine the removed skin under a microscope afterwards.


National Cancer Institute. Common Moles, Dysplastic Nevi, and Risk of Melanoma. Available at:

American Academy of Dermatology. Moles. Available at:

Cleveland Clinic. Moles, Freckles, Skin Tags, Lentigines, and Seborrheic Keratoses. Available at:

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