A hernia happens when an internal tissue or organ pushes through a weak spot in the muscle wall that normally holds it in place. Most commonly, this means a section of intestine or fatty tissue bulges through the abdominal wall, creating a visible lump under the skin. Hernias are extremely common: roughly 1 in 4 men will need surgery for a groin hernia at some point in their lives, compared to about 1 in 50 women.
How a Hernia Forms
Your abdominal organs are held in place by layers of muscle and a tough connective tissue called fascia. When that wall develops a gap or weak point, the lining of the abdominal cavity can form a sac that pokes through. That sac may contain fat, intestine, or other tissue. Some people are born with a weak spot that eventually gives way. Others develop one over time from repeated strain, surgery, or aging.
Common Types and Where They Appear
Hernias are named by their location, and each type behaves a little differently.
Inguinal hernias show up as a bulge in the groin, on one or both sides of the pubic bone. They’re the most common type by far, accounting for the majority of the roughly 770,000 groin hernia repairs performed each year in the United States. They can ache, pull, or feel heavy, especially when you lift something. In men, the bulging tissue sometimes descends into the scrotum, causing swelling and discomfort.
Femoral hernias appear in the upper thigh, just below the groin crease. They’re more common in women than men and tend to be sneaky: they aren’t always painful at first, but they’re riskier than inguinal hernias because they’re more likely to get trapped and lose blood supply.
Umbilical hernias develop near the belly button. They’re especially common in newborns and often close on their own within the first few years. Adults can develop them too, particularly during pregnancy or with significant weight gain.
Hiatal hernias are different from the rest because they happen inside the body, where part of the stomach pushes up through the diaphragm into the chest cavity. You won’t see a visible bulge. Instead, the main symptom is heartburn or acid reflux.
Incisional hernias form at the site of a previous surgical incision. About 1 in 4 people who have open abdominal surgery will eventually develop one. These account for a large share of the estimated 360,000 abdominal wall hernia repairs done annually in the U.S.
What a Hernia Feels Like
The classic sign is a bulge you can see or feel, often near the groin or belly button. It tends to become more obvious when you’re standing up, coughing, or straining. Many people describe a burning or aching sensation at the site, along with a feeling of pressure or heaviness, particularly when bending over or lifting.
In babies and young children, the signs can be subtler. A hernia may only appear when the child is crying, coughing, or straining during a bowel movement. The baby might seem unusually fussy or eat less than normal. In older children, the bulge is more noticeable after standing for a while or straining.
Some hernias cause no pain at all, especially early on. A hiatal hernia, for example, might only reveal itself through persistent heartburn. Small inguinal hernias can exist for years with nothing more than occasional mild discomfort.
Risk Factors That Weaken the Muscle Wall
Several things increase your odds of developing a hernia. Excess body weight is one of the biggest contributors for abdominal wall hernias. A BMI above 30 roughly doubles the probability of developing one. The reason is mechanical: every one-point increase in BMI raises pressure inside the abdomen by about 10%, steadily pushing against the muscle wall. Interestingly, higher BMI actually appears to lower the risk of inguinal (groin) hernias, likely because extra abdominal fat compresses the groin canal.
Other risk factors include chronic coughing, chronic constipation (repeated straining), heavy lifting over time, pregnancy, and a family history of hernias. Previous abdominal surgery creates a known weak point. Aging plays a role too, as connective tissue naturally loses strength over the years.
How Hernias Are Diagnosed
Most hernias are diagnosed with a simple physical exam. Your doctor will look for a visible bulge and may ask you to stand, cough, or bear down to make it more obvious. For groin hernias in particular, a physical exam is often all that’s needed.
When the diagnosis isn’t clear, such as when there’s pain but no visible bulge, imaging can help. Ultrasound is the preferred first choice because it has the highest accuracy for detecting groin hernias and is quick, painless, and widely available. CT scans are sometimes used for more complex cases, especially when a doctor suspects an internal hernia or needs to plan surgery. The accuracy of ultrasound does depend on the skill of the person performing it, so CT may be a better option in some settings.
When a Hernia Becomes an Emergency
Most hernias are not dangerous, but they can become so. An incarcerated hernia means the tissue has gotten stuck in the muscle wall and can’t be pushed back in. If the trapped tissue then loses its blood supply, it becomes a strangulated hernia, which is a surgical emergency.
Warning signs of strangulation include:
- Sudden, severe pain in the abdomen or groin that keeps getting worse
- Nausea and vomiting
- A hernia bulge that changes color, turning red, purple, or darker than your normal skin tone
- Inability to pass gas or have a bowel movement
- Fever
If the skin over a hernia bulge turns pale and then darkens, that signals tissue is losing blood flow. This requires immediate emergency care.
Surgical Repair and What to Expect
Surgery is the only way to fix a hernia. They don’t heal on their own (with the exception of small umbilical hernias in infants). Not every hernia needs immediate repair. Small, painless hernias are sometimes monitored with a “watchful waiting” approach, but most will eventually require surgery because they tend to grow over time.
There are two main surgical approaches. Open repair involves a single incision near the hernia, through which the surgeon pushes the tissue back into place and reinforces the area, usually with a synthetic mesh. Laparoscopic repair uses several small incisions and a camera to guide the procedure from inside. Both approaches take roughly the same amount of operating time when general anesthesia is used.
Recovery timelines vary by the type of repair. For a standard groin hernia operation, whether laparoscopic or open, most surgeons recommend about two weeks of avoiding heavy physical strain. After open surgery for a larger abdominal wall or incisional hernia, the typical recommendation extends to four weeks. Complex repairs involving large defects or multiple previous surgeries may require anywhere from five to sixteen weeks before full activity, depending on the individual case.
Most people with desk jobs return to work within one to two weeks after a standard groin repair. Those with physically demanding jobs generally need the full recovery period before resuming heavy lifting. Prolonged rest beyond these windows isn’t usually helpful and can actually slow recovery by leading to deconditioning.