Congenital Nevus

What Is a Congenital Nevus?

A congenital nevus is a mole that is present at birth. Or it may appear the first few weeks or months after birth.

Congenital nevi are often:

  • Light to dark brown in color.
  • Round or oval-shaped.
  • Slightly raised.

Moles can be anywhere on the body but mostly form on the limbs and trunk.

They're a common type of birthmark that, in most cases, don't cause symptoms or need treatment.

But you should have a doctor with expertise in managing moles check your baby. At UPMC Children's Hospital of Pittsburgh, our dermatology experts can assess your child's moles and guide you through treatment options.


Congenital nevus causes

Melanocytes are the cells in your body that make pigment. When these cells group together, a mole forms. This can happen in the womb before your baby is born.

The mole may be small, medium, or very large.

Small and medium moles are the most common. Small moles appear on about 1 in every 100 newborns.

Symptoms & Diagnosis

Congenital Nevus Symptoms and Diagnosis

Congenital nevus symptoms

A congenital nevus normally doesn't have symptoms other than its physical presence.

In a newborn, the skin around the mole may be more sensitive than other skin.

As your baby grows, the mole will likely grow and may itch sometimes.

Some moles can also grow hair, especially during puberty.

The mole may become irritated and even bleed, but this is rare.

When should I see a doctor about my child's moles?

You should have a doctor check any moles on your child that are:

  • Changing in color or shape.
  • Getting larger.
  • Itching.
  • Bleeding.

A giant congenital nevus — or giant congenital melanocytic nevus — is a larger, more noticeable type of mole.

These lesions can grow to be quite large and may carry a slightly higher risk of skin cancer later in life.

Congenital nevus diagnosis

Doctors can diagnose a congenital nevus by looking at it.

Your child's doctor will likely measure the mole and watch for any changes as your child grows.


Congenital Nevus Treatment

Most moles don't cause problems, and many don't need surgery to remove them.

But your child's doctor will need to check the mole over time. They'll watch for any changes that may signal a future risk of skin cancer.

If your child worries because of the mole's appearance or location, you can talk to your doctor about removal.

Surgery to remove a mole can leave some scarring. You should take that into account as you weigh the risks and benefits of treatment.

The best way to know your options is to have a surgeon assess your child and discuss treatment with them.

Surgery to remove a mole

Surgical excision, which removes the mole with a scalpel, is the most common treatment.

If the mole is very large, surgeons may not be able to remove it all in one step. They may take a few smaller steps to reduce its size and make future complete removal easier.

Surgeons call this approach a staged excision.

For young children with very large moles, your doctor may use a tissue expander. This allows your child to grow new skin that can replace tissue removed with the mole.

Contact Us

Meet our team at UPMC Children's Hospital of Pittsburgh's Cleft-Craniofacial Center and learn about our treatment options, or contact UPMC Children's Hospital of Pittsburgh at 412-692-8650.