A groin hernia happens when tissue, usually a loop of intestine or fatty tissue, pushes through a weak spot in the lower abdominal wall. This weak spot exists because the groin contains natural openings called inguinal canals, passages through the muscle layer that are present in everyone but are inherently vulnerable to pressure from inside the abdomen. About 27% of men and 3% of women will develop a groin hernia in their lifetime, making it one of the most common surgical conditions.
The Built-In Weakness in Your Groin
Your lower abdominal wall isn’t a seamless sheet of muscle. On each side of the groin, there’s a passage called the inguinal canal. In men, this canal carries the cord that supports the testicle. In women, it holds a ligament that supports the uterus. These canals create natural gaps in an otherwise strong muscular wall, and those gaps are where hernias tend to form.
There’s also a deeper passage on each side called the femoral canal, which carries blood vessels to the leg. Hernias that push through this route are called femoral hernias. They’re far more common in women, particularly older women, because the wider shape of the female pelvis creates a larger femoral canal opening.
Two Types With Different Origins
Groin hernias come in two main varieties, and they develop for different reasons.
An indirect inguinal hernia enters through the top of the inguinal canal. This type is typically rooted in a birth defect. During fetal development, the inguinal canals have openings inside the abdomen that normally close before birth. When one or both openings fail to close completely, abdominal contents can bulge through later in life. This is why indirect hernias can show up in infants and children, though they also appear in adults whose partially open canal finally gives way under pressure.
A direct inguinal hernia pushes straight through the wall of the inguinal canal itself. This type develops over time in adults as abdominal muscles weaken with age while chronic pressure on the muscle wall gradually forces tissue through. Direct hernias are almost exclusively an adult problem and become more common after middle age.
What Increases the Pressure
A weak spot in the abdominal wall is only half the equation. The other half is anything that repeatedly or continuously increases pressure inside your abdomen, pushing tissue toward that weak point. The most common culprits include:
- Chronic coughing, especially from smoking, which forces repeated bursts of pressure against the abdominal wall
- Straining during bowel movements, often from long-lasting constipation
- Heavy lifting or physically demanding work that involves standing or walking for many hours each day
- Pregnancy, which both weakens the abdominal muscles and increases pressure inside the abdomen
- Straining during urination, which can result from an enlarged prostate or other urinary conditions
None of these activities “cause” a hernia on their own. They work alongside an existing weakness, whether that weakness was present from birth or developed gradually over decades.
Why Men Are Far More Affected
Men develop inguinal hernias roughly nine times more often than women, and the reason traces back to fetal development. During pregnancy, the testicles form inside the abdomen and then descend through the inguinal canal into the scrotum. This descent creates a larger, more vulnerable opening in the abdominal wall compared to the smaller canal in women. Even when the canal closes properly after the testicles pass through, the area remains structurally weaker than the surrounding muscle.
When the canal doesn’t close fully, the risk is even higher. Premature infants are especially prone to indirect inguinal hernias because the canal has had less time to close before birth.
Connective Tissue and Genetics
Some people are biologically predisposed to groin hernias because of how their bodies build and maintain connective tissue. Research has found that people with inguinal hernias have measurably different collagen in the tissue that reinforces their abdominal wall. One study found 17.3% less total collagen and 23.7% less of the strongest type of collagen in the connective tissue of people with indirect inguinal hernias compared to people without hernias.
People with hernias also tend to have a higher proportion of a thinner, less mature form of collagen that provides less structural strength. This altered ratio appears in both direct and indirect hernias, suggesting a shared underlying connective tissue problem rather than two completely separate conditions. Reduced collagen and elastin have been found not just at the hernia site but in surrounding tissues as well, pointing to a broader, possibly inherited weakness in the body’s structural proteins.
Inherited connective tissue disorders like Ehlers-Danlos syndrome, which directly affects collagen metabolism, carry an increased risk of inguinal hernias and recurrent hernias after surgical repair. Marfan syndrome, which affects the scaffolding proteins that support connective tissue, raises similar concerns.
What Happens if a Hernia Is Left Alone
Most groin hernias start small and may cause only a visible bulge or mild discomfort, particularly when coughing, bending, or lifting. The bulge often disappears when you lie down. Many people live with a hernia for months or years without serious problems.
The main concern with an untreated hernia is that the protruding tissue can become trapped (incarcerated) and lose its blood supply (strangulated). This is a surgical emergency. However, the actual risk is lower than many people assume. Two large clinical trials comparing elective surgery with watchful waiting found that the rate of strangulation was less than 1% per year, ranging from 0.18% to 0.79% per patient-year in the first several years after the hernia appeared. The risk does mean that any sudden, severe groin pain with nausea or an inability to push the bulge back in warrants immediate medical attention.
Sports Hernias Are Something Different
If your groin pain started during athletics but you don’t have an obvious bulge, you may be dealing with what’s commonly called a “sports hernia.” Despite the name, this isn’t a true hernia. It’s a tear or weakening of the lower abdominal muscles or the tendons connecting muscles to the pelvis. Unlike an inguinal hernia, there’s typically no intestine protruding through the abdominal wall. The term is a misnomer that can cause confusion, and distinguishing between the two usually requires imaging such as MRI or ultrasound.