A hernia can cause problems ranging from mild groin discomfort to life-threatening emergencies like bowel strangulation, depending on its type, size, and whether tissue becomes trapped. Most hernias start with a visible bulge and some aching, but left alone, they can lead to intestinal blockage, chronic pain, acid reflux damage, and even bladder or kidney problems.
Everyday Symptoms of a Hernia
The most common thing a hernia causes is a noticeable bulge, typically in the groin or abdomen, that becomes more obvious when you stand up, cough, or strain. Along with the bulge, you may feel a burning or aching sensation at the site, along with pressure or discomfort that worsens when bending over, lifting, or coughing. In men, a groin hernia can push intestinal tissue down into the scrotum, causing pain and swelling around the testicles.
These symptoms tend to come and go early on. Many people find the bulge disappears when they lie down, then reappears with activity. Over time, though, the opening in the muscle wall often widens, allowing more tissue to push through and making symptoms more persistent.
Bowel Obstruction
One of the more serious things a hernia can cause is a bowel obstruction. This happens when a loop of intestine pushes through the hernia opening and gets trapped or tightly pinched, blocking the normal passage of food and waste. A partial blockage may cause cramping, bloating, and nausea. A complete blockage is more severe: you won’t be able to pass gas or have a bowel movement at all, and vomiting typically follows as pressure builds behind the blockage.
Bowel obstruction from a hernia requires emergency treatment. The trapped intestine needs to be freed, and the hernia repaired, before the tissue is permanently damaged.
Strangulation and Tissue Death
Strangulation is the most dangerous complication a hernia can cause. It occurs when trapped tissue loses its blood supply because the hernia opening squeezes it too tightly. Without blood flow, the tissue begins to die. Warning signs include sudden, severe pain that keeps getting worse, nausea and vomiting, and skin color changes around the bulge. The skin may first turn paler than usual, then shift to a reddish or darker color.
The overall risk of strangulation is relatively low for inguinal (groin) hernias, estimated at less than 1% per year based on clinical trials tracking patients over several years. Rates in those studies ranged from about 0.18% to 0.79% per patient-year. That said, the consequences are severe enough that any signs of strangulation warrant an immediate trip to the emergency room. Dead bowel tissue can lead to a perforated intestine, widespread infection, and sepsis.
Acid Reflux and Esophageal Damage
Not all hernias involve the groin. A hiatal hernia occurs when part of the stomach pushes up through the diaphragm into the chest cavity, and this type causes a completely different set of problems. The main one is chronic acid reflux, because the displaced stomach allows acid to flow back into the esophagus more easily.
Over months and years, persistent acid exposure can inflame and damage the lining of the esophagus. One recognized complication is Barrett’s esophagus, a condition where chronic inflammation triggers changes in the esophageal tissue. Barrett’s esophagus itself doesn’t cause symptoms, but it’s considered precancerous and requires ongoing monitoring. A large hiatal hernia can also compress the lungs enough to cause shortness of breath, particularly after eating or when lying down.
Bladder and Urinary Problems
In less common cases, a hernia can pull part of the bladder wall into the inguinal canal or femoral canal. When this happens, it can cause urinary symptoms: increased frequency, a weak or intermittent stream, straining to urinate, and taking longer than usual to empty the bladder. Some people find they need to physically press on the hernia bulge to finish urinating. Symptoms generally worsen as the herniation grows larger.
The complications of a bladder hernia go beyond inconvenience. The trapped bladder tissue can obstruct the flow of urine back from the kidneys, potentially causing acute kidney injury. Other possible complications include urinary tract infections and, in rare cases, loss of blood supply to the bladder tissue itself.
Post-Surgical Hernias
Incisional hernias develop at the site of a previous abdominal surgery, where the muscle wall was cut and never fully healed. Small ones may cause only mild bulging, but large incisional hernias carry the same risks of incarceration and strangulation as other types. The intestine can push through the weak surgical site, become trapped, and lose blood flow. The warning signs are identical: sudden severe pain, skin color changes over the bulge, nausea, and vomiting.
What Happens Without Treatment
Many people with small, painless hernias wonder whether they actually need to do anything about them. Research supports watchful waiting as a reasonable option for hernias that cause no symptoms or only mild discomfort, particularly in men over 50. But the picture changes over time. A 12-year follow-up study found that about 64% of men initially assigned to watchful waiting eventually crossed over to surgery because their hernia worsened. Among those with mild symptoms at the start, the crossover rate was even higher at nearly 72%, and half of them needed surgery within just two years.
People who chose to wait also reported more regret about their decision (about 38%) compared to those who had early surgery (18%), and they experienced more ongoing pain and discomfort. Hernias don’t heal on their own, and the muscle opening tends to widen over time, which is why even painless hernias are worth monitoring closely.
Signs That Need Emergency Attention
Most hernia symptoms develop gradually, but certain signs indicate a medical emergency. These include sudden, severe abdominal or groin pain that intensifies rather than easing up, nausea and vomiting alongside a painful hernia bulge, inability to pass gas or have a bowel movement, and visible skin color changes over the hernia site. If the skin shifts from pale to dark or reddish, that suggests the trapped tissue is losing blood flow and time matters. These symptoms together point to incarceration or strangulation, both of which require emergency surgery to prevent permanent damage to the bowel or other trapped tissue.