Lower abdominal pain has dozens of possible causes, ranging from mild muscle strain to conditions that need emergency treatment. The organs packed into your lower abdomen include parts of your intestines, your bladder, your appendix, and (depending on your sex) your uterus and ovaries or your prostate. Pain in this area usually traces back to one of three systems: digestive, urinary, or reproductive.
Where the Pain Is Matters
The lower abdomen is broadly split into right and left sides, and the location of your pain is one of the strongest clues to what’s causing it. Pain in the lower right side raises concern for appendicitis, especially if it started near your belly button and migrated downward over several hours. Appendicitis affects roughly 7 to 8 percent of people at some point in their lifetime, making it one of the most common surgical emergencies.
Pain in the lower left side is most often related to diverticulosis or diverticulitis. Diverticula are small pouches that form in the wall of the colon, and they tend to develop on the left side. When one of those pouches becomes inflamed or infected, the result is a steady, sometimes severe ache in your lower left abdomen, often accompanied by fever or changes in bowel habits.
Pain that sits low and central, just above the pubic bone, usually points to the bladder or, in women, the uterus. And pain that seems to shift around or affect both sides can signal a bowel issue like irritable bowel syndrome, inflammatory bowel disease, or simple gas and constipation.
Digestive Causes
Your intestines take up most of the real estate in your lower abdomen, so digestive problems are the most frequent source of pain there. Constipation alone can produce surprisingly intense cramping, especially on the left side where stool tends to accumulate before a bowel movement. Gas trapped in a loop of bowel can mimic sharper conditions and then resolve on its own within hours.
Irritable bowel syndrome is one of the most common chronic causes. To qualify for a formal diagnosis, the pattern needs to be specific: recurring abdominal pain at least one day per week for three months, linked to bowel movements or a noticeable change in how often you go or what your stool looks like. Symptoms must have started at least six months before diagnosis. IBS pain often improves after a bowel movement and worsens with stress or certain foods.
Inflammatory bowel disease (Crohn’s disease and ulcerative colitis) produces pain that tends to be more persistent and is often accompanied by bloody stool, weight loss, or fatigue. Crohn’s disease in particular can affect the lower right abdomen, where the end of the small intestine meets the colon. Appendicitis, colitis, and diverticulitis round out the list of more acute digestive causes that can flare up suddenly and escalate quickly.
Urinary Tract Causes
A urinary tract infection typically causes a burning sensation when you urinate, a frequent or urgent need to go, and a dull ache or pressure in your lower abdomen just above the pubic bone. The urine may look cloudy or smell unusual. If the infection travels up to the kidneys, the pain shifts to your side and back below the ribs, and you may develop fever, chills, nausea, or vomiting.
Kidney stones produce a different pattern. The pain is often described as coming in waves, sometimes intensely sharp, starting in the back and radiating down toward the lower abdomen and groin as the stone moves through the urinary tract. You might notice pink, red, or brown urine. The pain can shift location as the stone travels, and it tends to spike when a stone gets stuck in the narrow tube connecting your kidney to your bladder, causing the kidney to swell and the tube to spasm. Nausea and vomiting are common with larger stones.
Reproductive Causes in Women
The uterus, ovaries, and fallopian tubes sit in the lower abdomen, which means menstrual cramps, ovulation pain, and ovarian cysts are among the most common reasons women experience pain in this area. Ovulation pain (sometimes called mittelschmerz) happens midway through the menstrual cycle when an egg is released, and it typically affects one side for a few hours to a day or two.
Ovarian cysts can rupture and cause a sudden, sharp pain on one side of the lower abdomen. The pain usually resolves on its own but can be severe enough to mimic an emergency. A more serious condition, ovarian torsion, occurs when an ovary twists on itself and cuts off its own blood supply. This produces sudden, intense pain often with nausea, and it requires emergency treatment.
Pelvic inflammatory disease is an infection of the reproductive organs, usually caused by sexually transmitted bacteria. It produces a deep, steady ache in the lower abdomen along with unusual discharge, pain during sex, and sometimes fever. Ectopic pregnancy, where a fertilized egg implants outside the uterus (typically in a fallopian tube), causes one-sided lower abdominal pain that can become life-threatening if the tube ruptures. Any lower abdominal pain with a missed period or abnormal bleeding warrants a pregnancy test.
Causes Specific to Men
Inguinal hernias are far more common in men than women. A hernia occurs when a portion of the small intestine pushes through a weak spot in the lower abdominal wall, creating a painful or tender lump on one or both sides of the groin. Lifting heavy objects, coughing, sneezing, or exercising tends to make it worse. Some hernias are small and manageable, but if the bulging tissue gets trapped and its blood supply is cut off, it becomes a surgical emergency.
Prostatitis, or inflammation of the prostate gland, can cause aching in the lower abdomen and upper thighs. It sometimes comes with difficulty urinating, a frequent need to urinate, or pain during ejaculation. Testicular torsion, where a testicle twists on its cord, produces sudden, intense pain that starts in the scrotum and spreads up into the groin and lower abdomen. The scrotum may swell. This is a time-sensitive emergency because the testicle can lose blood supply within hours.
Signs That Need Emergency Attention
Most lower abdominal pain resolves on its own or with simple treatment. But certain patterns signal something that needs immediate evaluation. If pain is severe enough to interrupt your ability to function, that alone is a reason to go to the emergency room. The same applies if you’re unable to keep liquids down due to persistent vomiting, if you’re completely unable to pass gas or have a bowel movement alongside worsening pain, or if you’ve had prior abdominal surgery and the current pain feels different or more intense than what you’ve experienced before.
Appendicitis has a recognizable progression: pain that begins near the belly button, then moves lower and to the right, worsening over hours. It gets worse when you move, cough, sneeze, or take deep breaths. Other warning signs include loss of appetite, nausea, fever, abdominal swelling, and constipation or diarrhea. This combination, especially in someone who has never had their appendix removed, warrants an ER visit rather than a wait-and-see approach.
What Doctors Look For
When you see a provider for lower abdominal pain, the first step is usually a detailed conversation about where the pain is, when it started, what makes it better or worse, and whether it came on gradually or suddenly. The physical exam involves pressing on different areas of your abdomen to identify the exact spot of tenderness. If pain shows up in an area that doesn’t match your described symptoms, your doctor may gently pinch the abdominal muscles to check whether the issue is actually in the muscle wall rather than an internal organ.
Depending on the suspected cause, you may need blood work, a urine test, imaging like an ultrasound or CT scan, or (for women) a pregnancy test. The combination of your pain’s location, its timing, your other symptoms, and the exam findings is usually enough to narrow down the cause and determine next steps.