The belly button, or umbilicus, is a scar that forms after the umbilical cord detaches shortly after birth. While most people develop an “innie,” around 10% of the population has an “outie”—a belly button that protrudes outward.

Outies are usually harmless and happen naturally during healing, but they can also be linked to certain medical conditions such as hernias or granulomas. They may also appear temporarily in adulthood due to pregnancy or abdominal swelling. Understanding the causes and when to seek medical care is important for both health and cosmetic reasons.

What an Outie Belly Button Looks Like

appearance

  • Outies often appear round, button-like, or knot-shaped, protruding slightly above the skin.

  • They may feature a mamelon (a central raised portion) and sometimes a small fold of tissue called a cushion.

  • The scar tissue may form crisscross lines, giving it a distinctive texture.

feel and changes over time

  • Outies usually feel firm compared to surrounding skin.

  • With age, the surrounding tissue may loosen, making the area appear more saggy.

Causes of an Outie Belly Button

Natural Development

The healing process of the umbilical stump is unpredictable. Some scars heal inward (innies), while others form outward (outies). This is not influenced by how the cord was cut or how the stump was cared for—it simply depends on how the scar tissue formed.

Umbilical Hernia

An umbilical hernia occurs when the abdominal muscles fail to close completely after birth, allowing the intestines to push through and create a bulge.

key features

  • Bulge becomes more visible when crying, coughing, or straining.

  • Usually resolves on its own in children by age five.

  • In rare cases, the hernia becomes “strangulated,” cutting off blood supply—this requires urgent surgery.

Adults can also develop umbilical hernias due to weakened abdominal walls, heavy lifting, or obesity.

Umbilical Granuloma

A small growth of inflamed tissue can appear after the umbilical stump falls off.

  • Usually pink or red with possible fluid discharge.

  • Often heals with minimal care but can become infected if not monitored.

  • Treatments include silver nitrate, cryotherapy, or surgical removal if persistent.

Umbilical Polyp

Unlike granulomas, polyps are congenital (present from birth) and result from remnants of embryonic tissue.

  • Appear as firm, red lumps at the navel.

  • Do not heal on their own and require surgical removal.

Acquired Outies in Adulthood

Some people develop outie belly buttons later in life.

common triggers

  • pregnancy: As the uterus expands, pressure pushes the belly button outward (often temporary).

  • ascites: Fluid buildup in the abdomen, often related to liver or kidney disease.

  • umbilical hernia in adults: Weakness in the abdominal wall may create a bulge.

  • piercing-related granuloma: Poor healing after a navel piercing can cause tissue overgrowth.

When to See a Healthcare Provider

Most outie belly buttons are harmless. However, medical evaluation is needed if you or your child experience:

  • Persistent pain, fever, or vomiting alongside a bulging navel

  • Redness, swelling, or discharge from the belly button

  • Severe or enlarging umbilical hernia

  • Bleeding or signs of infection in newborns after stump detachment

An exam and imaging may be performed, and treatment depends on whether the cause is cosmetic or medical.

Treatment Options

Most outies don’t require treatment unless they’re causing health problems or someone wishes to change the appearance.

medical and surgical treatments

  • umbilicoplasty: Elective surgery to reshape the belly button for cosmetic reasons.

  • hernia repair: Surgical reinforcement of weakened abdominal tissue.

  • granuloma removal: Silver nitrate application, cryotherapy, electrocautery, or surgical ligation.

  • polyp removal: Surgical resection is the only effective method.

Preventing Outie Belly Buttons

Since outies usually form randomly during healing, they cannot be prevented. However, proper newborn umbilical stump care reduces complications:

  • Allow the stump to dry and fall off naturally.

  • Avoid pulling or tugging at the stump.

  • Keep the area clean and dry, using only damp gauze if necessary.

  • Use sponge baths until the stump detaches fully.

For adults, prevention focuses on managing risk factors for hernias and ascites: maintaining a healthy weight, avoiding heavy straining, and treating chronic liver or kidney issues.

Quick Summary

Outie belly buttons are typically harmless scars formed after the umbilical cord detaches. They develop naturally in about 10% of people, but they can also be linked to conditions like hernias, granulomas, or polyps.

Most cases are only cosmetic and require no treatment. However, when outies are caused by hernias, persistent lumps, or infections, medical evaluation and possible surgery may be necessary.