A groin hernia develops when tissue, usually part of the intestine or the fatty lining of the abdomen, pushes through a weak spot in the lower abdominal wall. About 27% of men and 3% of women will develop one in their lifetime. The weakness can be something you’re born with or something that develops over years of strain, and understanding the specific causes helps explain why groin hernias are so common.
What Happens Inside the Abdominal Wall
Your lower abdomen has a natural passageway called the inguinal canal, a tube about four to six centimeters long that runs through layers of muscle and connective tissue just above the groin crease. In men, this canal carries the spermatic cord to the testicles. In women, it holds a ligament that supports the uterus. The canal has an internal opening (deep ring) and an external opening (superficial ring), with several layers of muscle and tissue forming its walls, floor, and roof.
A hernia occurs when something pushes through a gap in one of those layers. The tissue that lines your abdominal cavity stretches outward like a small sac, and intestine or abdominal fat can slide into it. You might picture it like a weak spot in an inner tube: pressure from inside eventually forces the lining to balloon out through the thinnest point.
The Two Main Types of Groin Hernia
Not all groin hernias form the same way. The two most common types involve the inguinal canal but enter it through different routes.
Indirect inguinal hernia: This type enters the canal through the deep ring at the top and follows the canal’s natural path downward. It’s usually tied to a structural issue present from birth. During fetal development, a small sleeve of tissue called the processus vaginalis extends through the inguinal canal. It normally closes off before or shortly after birth. But in up to 40% of males older than two, this sleeve never fully closes. That leftover opening creates a ready-made path for abdominal contents to slip through later in life. About 90% of indirect inguinal hernias in adults trace back to this persistent opening. In men, the hernia can follow the canal all the way down into the scrotum.
Direct inguinal hernia: This type pushes straight through a weakened area in the back wall of the canal itself, rather than entering through the deep ring. It develops over time as abdominal muscles thin out with age and sustained pressure. Direct hernias are almost exclusively seen in adults.
A third, less common type is the femoral hernia, which pushes through the femoral canal, a small space near the large blood vessels of the upper thigh. Femoral hernias account for roughly 3% of all groin hernias but are four times more common in women than in men, likely because of the wider shape of the female pelvis.
What Weakens the Abdominal Wall
Two things have to come together for a hernia to form: a weak spot in the muscle or connective tissue, and enough internal pressure to push something through it. Some people are born with that weak spot. Others develop it gradually.
Connective tissue naturally loses strength with age. Collagen, the protein that gives your abdominal wall its structural integrity, breaks down over the decades. This is why direct hernias are far more common in older adults. Smoking accelerates that breakdown significantly. One study found that smokers had roughly four times the risk of developing a hernia through weakened tissue compared to nonsmokers, independent of other risk factors. The chemicals in cigarette smoke interfere with collagen production and repair throughout the body.
Family history also plays a role. If a close relative had a groin hernia, your connective tissue may share the same structural vulnerabilities.
Activities and Conditions That Increase Pressure
Anything that repeatedly raises the pressure inside your abdomen can force tissue through a weak point. The most well-established triggers include:
- Heavy or repetitive lifting: A meta-analysis of occupational studies found that physically demanding work more than doubled the odds of developing an inguinal hernia. Workers who lifted cumulative loads over 4,000 kilograms (about 8,800 pounds total) per workday had a measurably higher risk, as did those who stood or walked for more than six hours daily.
- Chronic coughing: Conditions like COPD, chronic bronchitis, or persistent asthma keep the abdominal muscles under repeated strain. Severe coughing generates enough force to tear muscle fibers over time.
- Straining during bowel movements: Chronic constipation forces you to bear down repeatedly, spiking pressure in the lower abdomen.
- Pregnancy: The growing uterus stretches and thins the abdominal wall while adding sustained pressure from the inside.
- Excess body weight: Carrying extra abdominal fat creates constant, low-grade pressure on the inguinal region.
None of these activities “cause” a hernia on their own. They exploit an existing weakness. That’s why two people can do the same job for twenty years and only one develops a hernia.
Why Men Get Groin Hernias Far More Often
Men develop inguinal hernias 9 to 12 times more often than women. The reason is largely anatomical. The inguinal canal in men needs to be wide enough for the spermatic cord and its blood vessels to pass through, which creates a naturally larger and more vulnerable opening. The processus vaginalis, the fetal tissue sleeve that should close after birth, is also more commonly persistent in males. Women have a smaller inguinal canal with a narrow ligament passing through it, so there’s less structural opportunity for tissue to protrude.
Women are more susceptible to femoral hernias, however, because the femoral canal is proportionally wider in the female pelvis.
What a Groin Hernia Feels Like
The earliest sign is usually a small bulge on one side of the pubic bone. It may appear only when you’re standing, coughing, or straining, and disappear when you lie down. Many people first notice it in the shower or while getting dressed.
Along with the visible bulge, you might feel a burning or aching sensation at the site, pressure or discomfort in the groin when bending over or lifting, or a dragging heaviness that worsens through the day. In men, the hernia can descend into the scrotum and cause pain or swelling around the testicle. Some hernias produce no pain at all and are found incidentally during a physical exam.
When a Hernia Becomes Dangerous
Most groin hernias are not emergencies, but two complications can make them one. An incarcerated hernia means the tissue that slipped through has become trapped and can’t be pushed back in. This blocks the normal flow of the intestine. A strangulated hernia is more serious: the trapped tissue loses its blood supply entirely, which can lead to tissue death within hours.
Signs of strangulation include sudden, severe pain at the hernia site, nausea or vomiting, fever, and a bulge that turns red, purple, or dark. A strangulated hernia requires emergency surgery.
Hernias do not heal on their own. The opening in the muscle wall will not close without surgical repair, and most hernias gradually enlarge over time. Small, painless hernias can sometimes be monitored, but a hernia that causes symptoms or is growing will eventually need to be repaired.