The belly button, or umbilicus, is a natural part of human anatomy. During pregnancy, the umbilical cord acts as a conduit, delivering oxygen and nutrients to the developing fetus. After birth, this cord is clamped and cut, leaving behind a small stump that eventually dries and falls off, forming the unique shape of each individual’s navel. This transforms a vital connection into a distinct feature.
Understanding a Protruding Belly Button
A protruding belly button can sometimes be a normal variation in appearance, often called an “outie.” This occurs due to the way the skin heals after the umbilical cord stump detaches, and it is generally harmless. However, a belly button that protrudes can also indicate an umbilical hernia, a common condition where part of the intestine or other abdominal tissue bulges through a weak spot near the navel.
Umbilical hernias are particularly common in infants, affecting an estimated 10% to 20% of newborns. While the appearance of a bulge might cause concern, most umbilical hernias in children are painless and do not pose a serious threat. The size of the protrusion can vary, and it may not always be visible, often appearing more prominent under certain conditions.
Common Timing and Contributing Factors
Umbilical hernias are most frequently observed in infants. This occurs because, during fetal development, the umbilical cord passes through a small opening in the abdominal muscles, known as the umbilical ring. Normally, this opening closes completely shortly after birth. An umbilical hernia develops if these abdominal muscles do not fully join together, leaving a small gap through which internal tissues can protrude.
Certain factors can make an umbilical hernia more noticeable, such as increased pressure within the abdomen. This pressure can occur when a baby cries, coughs, strains during a bowel movement, or even stands up. These actions do not cause the hernia but make an existing one more evident. Hernias are more common in premature babies, those with low birth weight, and infants with certain genetic conditions, though they can affect any child. In adults, umbilical hernias are less common but can arise from conditions that increase abdominal pressure, such as obesity, multiple pregnancies, chronic coughing, or straining from constipation or heavy lifting.
When to Seek Medical Advice
For most children, an umbilical hernia will resolve on its own without intervention. Approximately 90% of umbilical hernias spontaneously close, often by the age of two. However, there are specific signs that warrant prompt medical evaluation. Consult a healthcare professional if the belly button bulge becomes hard, tender to the touch, red, purple, or discolored.
Signs of discomfort or pain, particularly if sudden or worsening, require immediate attention. Other concerning symptoms include vomiting, constipation, a swollen abdomen, or increased irritability, which could indicate that a portion of the intestine has become trapped within the hernia opening. If the hernia cannot be gently pushed back into the abdomen, it is considered incarcerated and needs urgent medical assessment to prevent potential complications such as restricted blood supply to the trapped tissue. If the hernia has not closed on its own by age four or five, or if it is notably large, consider repair.