Why a baby's belly button bulge is often a temporary milestone

Health · Published 19 October 2026 Swipe more like this →

In short: Most newborns are born with a small lump at their navel. While it looks like a structural flaw, it is often just a byproduct of fetal development. For children, these hernias usually resolve on their own, but for adults, the underlying mechanics change significantly.

Umbilical hernias occur when the opening for the umbilical cord—the umbilical ring—fails to close completely after birth. During fetal development, organs form outside the abdominal cavity and return through this opening. Because the ring is still maturing in newborns, the abdominal lining and bowel can bulge outward to form a soft lump. While children are more likely to have these hernias, they are common, affecting about six in 100 children, with a higher prevalence in boys.

The clinical progression of these hernias depends heavily on age. In infants, the opening typically closes on its own, often by age five, and many resolve by age three. Because of this natural healing, doctors usually only suggest surgery for children if the hernia persists past age three. In contrast, adults rarely see these hernias resolve spontaneously. In adults, the condition is often 'acquired' rather than congenital, driven by increased intra-abdominal pressure from factors like obesity, multiple pregnancies, liver disease (causing fluid buildup called ascites), or previous abdominal surgeries.

While often harmless, hernias can transition from minor nuisances to medical emergencies. In adults, they may cause dull pain or pressure, especially when coughing or straining. The most serious risk is a 'strangulated' hernia, where the blood supply to the trapped tissue is cut off. This is a medical emergency that can lead to sepsis or gangrene. Surgery for adults is typically recommended unless the patient is too unwell to undergo anesthesia, while children's repairs are often performed as day surgeries lasting between 30 and 60 minutes.

General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.

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