Lower stomach pain has dozens of possible causes, ranging from a pulled muscle to a serious infection. Where exactly you feel the pain, how long it lasts, and what other symptoms come with it are the best clues to narrowing down what’s going on. Most cases trace back to digestive issues, urinary tract problems, or (in women) reproductive conditions, but the location and quality of the pain matter more than you might expect.
Location Narrows the Cause Significantly
Your lower abdomen contains parts of the small and large intestines, the bladder, and (in women) the uterus and ovaries. Pain on the right side points to a different set of conditions than pain on the left, and pain in the center just above the pubic bone suggests something else entirely. Paying attention to exactly where the pain concentrates gives you and your doctor the most useful starting point.
Right lower pain is most associated with appendicitis, ovarian cysts, and in some cases the early stages of Crohn’s disease. Left lower pain is the classic location for diverticulitis and constipation-related cramping. Central lower pain, sometimes called suprapubic pain, often comes from the bladder or uterus.
Digestive Causes: The Most Common Culprits
Constipation and Gas
The simplest explanation is often the right one. Trapped gas and backed-up stool create real, sometimes intense pressure in the lower abdomen. This type of pain tends to come in waves, shift locations slightly, and improve after a bowel movement or passing gas. If you’ve recently changed your diet, traveled, or been less active than usual, constipation is a likely suspect.
Irritable Bowel Syndrome
IBS affects between 4% and 9% of the global population and is one of the most common reasons for chronic lower abdominal pain. The hallmark pattern is recurring pain for at least 12 weeks out of the past year, accompanied by changes in how often you go to the bathroom or changes in stool consistency. Many people notice symptoms flare after large meals or during stressful periods, and the pain often eases temporarily after a bowel movement. IBS does not cause inflammation or permanent damage to the intestines, which is what separates it from inflammatory bowel disease.
If your pain comes with bleeding, unexplained weight loss, fever, or anemia, that points toward inflammatory bowel disease (conditions like Crohn’s disease or ulcerative colitis) rather than IBS. These conditions cause visible damage to the intestinal lining and need different treatment.
Diverticulitis
Small pouches can form along the walls of the colon, especially after age 50. When one of those pouches becomes inflamed or infected, the result is diverticulitis. The pain is usually sudden and intense, concentrated in the lower left abdomen, and often accompanied by fever, nausea, and changes in bowel habits like sudden diarrhea or constipation. In some cases the pain starts mild and builds over several days, with the intensity fluctuating. Diverticulitis typically needs medical treatment and sometimes antibiotics.
Urinary Tract Infections
A bladder infection can cause a dull ache or pressure in the lower abdomen, right above the pubic bone. You’ll usually also notice burning during urination, a frequent urge to go, or cloudy and strong-smelling urine. UTIs are far more common in women than men and are usually straightforward to diagnose with a urine test. The lower abdominal discomfort from a UTI typically resolves within a day or two of starting treatment.
Kidney stones produce a different kind of pain. It tends to start in the back or side and radiate forward and downward as the stone moves through the urinary tract. The pain is often severe and comes in sharp waves, which distinguishes it from the steady pressure of a bladder infection.
Reproductive Causes in Women
For women, the reproductive organs sit right in the lower abdomen, so conditions affecting the ovaries, uterus, or fallopian tubes frequently show up as lower stomach pain. Ovulation pain (a brief, sharp twinge on one side midway through the menstrual cycle) and menstrual cramps are the most common and least concerning versions.
Ovarian cysts can cause a persistent ache on one side of the lower abdomen. Most cysts resolve on their own within a few menstrual cycles, but a cyst that ruptures or twists can cause sudden, severe pain that needs immediate attention. Endometriosis, where tissue similar to the uterine lining grows outside the uterus, causes chronic pain that often worsens during periods and can include pain during sex.
Pelvic inflammatory disease is an infection of the reproductive organs, usually caused by sexually transmitted bacteria. It produces lower abdominal or pelvic pain along with abnormal vaginal discharge, unusual bleeding, and pain during sex. PID needs prompt treatment because untreated infection can cause lasting damage to the fallopian tubes and affect fertility.
An ectopic pregnancy, where a fertilized egg implants outside the uterus (usually in a fallopian tube), causes lower abdominal pain that can become severe. If you’re of reproductive age and have lower abdominal pain with a missed period, vaginal bleeding, or dizziness, this is a possibility that needs urgent evaluation.
Appendicitis: The One to Rule Out Quickly
Appendicitis follows a fairly recognizable pattern. The pain typically starts as a vague ache around the belly button, then migrates over several hours to the lower right abdomen. Vomiting usually comes after the pain begins, not before, and fever tends to develop 24 to 48 hours after the first symptoms. The pain gets worse with movement, coughing, or jarring motions.
A simple at-home clue: press firmly on the lower right area for 10 to 15 seconds, then release suddenly. If the sharp spike of pain hits when you let go (not while pressing), that’s called rebound tenderness and it’s one of the most reliable physical signs pointing toward appendicitis. This warrants an emergency room visit. CT scans are the most accurate imaging tool for confirming appendicitis, with about 75% sensitivity and 80% specificity, compared to roughly 70% and 63% for ultrasound.
Could It Be a Muscle Problem?
Abdominal wall pain from a strained muscle, a pinched nerve, or even overuse from exercise is surprisingly common and frequently mistaken for something internal. The key difference: muscle-related pain gets worse when you tense your abs (like doing a crunch or lifting your legs while lying down) and improves when you relax them. Internal organ pain behaves the opposite way, often feeling the same or slightly better when the abdominal muscles are tense because the contracted muscles act as a shield over the organs.
You can test this yourself by lying flat, pressing on the painful spot, then lifting your head as if doing a sit-up. If the pain increases while your abs are engaged, the problem is likely in the abdominal wall itself rather than inside. This type of pain usually responds well to rest, ice, and over-the-counter pain relief.
When Lower Stomach Pain Is an Emergency
Certain patterns of pain signal that something needs immediate attention. Get to an emergency room if the pain is severe enough to prevent you from functioning normally, if you’re vomiting and unable to keep liquids down, or if you’re unable to have a bowel movement and the pain is worsening. Pain accompanied by fever, bloody stool, or dizziness also warrants urgent care.
Pay special attention if the pain feels similar to something you’ve experienced before but is clearly more intense or behaving differently this time. A familiar pain that suddenly changes character can indicate a complication of a known condition.