Umbilical hernias are one of the most common types of hernias, affecting 10 to 15 percent of all newborns and a surprisingly large portion of adults. Over 175,000 umbilical hernia repairs are performed each year in the United States alone, making this a condition most surgeons see routinely.
How Common They Are in Infants
Roughly 1 in 7 to 1 in 10 babies is born with an umbilical hernia, and boys and girls are affected at equal rates. These hernias appear as a soft bulge near the belly button, caused by a small gap in the abdominal wall muscles where the umbilical cord passed through. In most cases, the opening simply hasn’t finished closing by the time the baby is born.
The good news for parents: the vast majority of these hernias resolve without any treatment. Research published in the New England Journal of Medicine found that 90% of small hernias (1 cm or less) and 80% of larger ones close on their own within five years. Most close by age 3, and those still open at that point often close by age 5. Surgery is typically only considered if the hernia persists past that window or causes problems sooner.
Prevalence in Adults
Adult umbilical hernias are far more common than most people realize. A study in the Journal of Surgical Research examined CT scans of 472 adults and found umbilical hernias in nearly 68% of them. That number is striking because the vast majority of those hernias had never been diagnosed. Many were small, produced no symptoms, and would never have been noticed without imaging.
This gap between what’s detected on a scan and what’s diagnosed in a clinic explains why umbilical hernias are considered commonly underdiagnosed. The hernias that do get medical attention are the ones large enough to see or feel, or the ones that start causing discomfort. The true prevalence in the general adult population is likely much higher than older estimates suggested.
Who Is Most at Risk
In adults, umbilical hernias develop when sustained pressure inside the abdomen pushes against a weak spot in the muscle wall near the navel. Several factors raise that risk significantly.
- Sex: Umbilical hernias are three times more common in women than in men.
- Obesity: Excess abdominal weight puts constant outward pressure on the muscle wall, making hernias more likely to develop and more likely to grow.
- Multiple pregnancies: Women who have given birth more than once face a higher risk, as repeated stretching of the abdominal wall weakens the tissue around the navel.
- Fluid buildup in the abdomen: People with liver cirrhosis can develop a condition where fluid accumulates in the abdominal cavity, creating the kind of internal pressure that forces tissue through weak points.
Other contributing factors include heavy lifting over time, chronic coughing, and any condition that causes prolonged straining. The common thread is repeated or sustained pressure against an area of the abdominal wall that was already a natural weak point from birth.
What Happens if You Leave One Alone
In children, watchful waiting is the standard approach because the overwhelming majority of hernias close naturally. In adults, the calculus is different. Adult umbilical hernias do not resolve on their own. The opening in the muscle wall either stays the same size or gradually widens over time.
The main concern with an untreated adult hernia is strangulation, where a loop of intestine gets trapped in the hernia and its blood supply is cut off. According to the American College of Surgeons, there is a 4% risk of strangulation within five years if an adult hernia is not surgically repaired. That may sound low, but strangulation is a surgical emergency that can lead to tissue death and serious complications within hours.
Many adults live with small, painless umbilical hernias for years without issues. The decision about whether and when to repair one depends on the size of the hernia, whether it’s growing, and whether it causes pain or limits activity. Hernias that are easily pushed back in and cause no symptoms carry less immediate urgency than those that are firm, tender, or getting bigger.
How Repair Surgery Works
Umbilical hernia repair is one of the most frequently performed general surgeries in the country, with more than 175,000 procedures done annually in the U.S. For most people, it’s an outpatient operation, meaning you go home the same day.
The surgeon pushes the protruding tissue back into place and closes the gap in the muscle wall, sometimes reinforcing it with a small piece of surgical mesh to reduce the chance of recurrence. Recovery typically takes one to two weeks for a return to normal daily activities, with heavier physical work restricted for four to six weeks. Most people describe the post-surgical discomfort as moderate soreness around the incision site that improves steadily over the first few days.
For small hernias repaired without mesh, there is a meaningful chance the hernia can come back over time. Mesh reinforcement lowers recurrence rates considerably, which is why it’s become the preferred approach for all but the smallest defects.