Lower abdominal pain has dozens of possible causes, ranging from trapped gas that resolves in hours to conditions that need emergency care. The most common culprits are digestive issues like constipation, gas, and indigestion, but the location, timing, and type of pain can point toward something more specific in your urinary tract, reproductive organs, or abdominal wall.
Common Digestive Causes
Gas, indigestion, constipation, and diarrhea are the most frequent reasons for lower abdominal discomfort. These tend to come and go, often feel crampy or bloated, and usually improve after a bowel movement or passing gas. If you’ve eaten something that disagreed with you, had a change in diet, or are stressed, this is the most likely explanation.
Irritable bowel syndrome (IBS) is worth considering if you’ve had recurring lower abdominal pain tied to changes in your bowel habits, whether that’s constipation, diarrhea, or both. IBS pain typically shows up at least once a week for three months or longer and is linked to how often or how easily you go. It’s not dangerous, but it can be disruptive enough to need management.
Food intolerances, particularly to lactose or gluten, can also produce cramping in the lower abdomen along with bloating and loose stools. Celiac disease, an immune reaction to gluten, causes inflammation in the small intestine and can be confirmed with blood tests.
Pain on the Lower Left Side
If the pain is concentrated on your lower left side, the most likely digestive cause is diverticulitis. Small pouches called diverticula can form in the wall of the colon, and they almost always develop in the lower left portion. Many people have these pouches without knowing it. But when one becomes inflamed or infected, it causes steady, often sharp pain in the lower left abdomen, sometimes with fever, nausea, or a change in bowel habits.
Mild diverticulitis can sometimes be managed without antibiotics in otherwise healthy people, though antibiotics are used when there are signs of infection or when the patient has other health conditions. Diagnosis typically involves a CT scan to confirm the inflammation and check for complications. Severe cases with abscess formation or signs of spreading infection may require drainage procedures or surgery.
Pain on the Lower Right Side
Lower right abdominal pain raises concern for appendicitis, especially if it came on suddenly and has gotten steadily worse over several hours. The classic pattern starts as vague discomfort around the belly button, then migrates to the lower right side and sharpens. Fever, nausea, and loss of appetite often follow. If you have severe pain in this area, go to the emergency room. A ruptured appendix can cause a life-threatening infection.
Not all lower right pain is appendicitis. Muscle strain, trapped gas, and even constipation can produce discomfort in the same area. The key difference is the trajectory: appendicitis pain gets progressively worse over hours rather than coming and going.
Urinary Tract Causes
A bladder infection (the most common type of urinary tract infection) frequently causes pain or pressure in the lower abdomen, centered behind the pubic bone. You’ll usually also notice burning with urination, a frequent urge to go, or cloudy and strong-smelling urine. UTIs are far more common in women but can affect anyone.
Kidney stones can also produce lower abdominal pain, though they more often start as intense pain in the back or side that radiates downward toward the groin as the stone moves through the urinary tract. The pain tends to come in waves and can be severe enough to cause nausea or vomiting. A stone usually affects one side at a time.
Causes Specific to Women
The reproductive organs sit in the lower abdomen, so conditions affecting the uterus, ovaries, or fallopian tubes commonly show up as pain in this area.
Ovulation pain happens midway through the menstrual cycle when an ovarian follicle ruptures to release an egg. It’s typically one-sided, lasts a few hours to a day, and is harmless. Many women experience this monthly without realizing it has a name.
Ovarian cysts are fluid-filled sacs that develop on the ovaries, often during the menstrual cycle. Most resolve on their own, but larger cysts can cause one-sided lower abdominal pain that sometimes radiates to the lower back. A cyst that twists (ovarian torsion) causes sudden, severe pain and is a surgical emergency, accounting for roughly 3 to 7 percent of gynecological emergencies.
Endometriosis affects an estimated 10 to 15 percent of women of reproductive age. Tissue similar to the uterine lining grows outside the uterus, causing inflammation, adhesions, and pain that tends to worsen around menstruation. It’s most commonly diagnosed in women in their 30s, though symptoms often start years earlier.
Pelvic inflammatory disease is an infection of the upper reproductive tract, usually caused by sexually transmitted bacteria. It typically produces bilateral (both sides) lower abdominal pain along with abnormal vaginal discharge, pain during sex, or unusual bleeding between periods. Prompt treatment prevents long-term complications like scarring and fertility problems.
Causes Specific to Men
Inguinal hernias are among the most common causes of lower abdominal and groin pain in men. A hernia occurs when tissue, often part of the intestine, pushes through a weak spot in the abdominal wall near the groin. You might notice a bulge on either side of the pubic bone that becomes more obvious when you stand up, cough, or strain. The area can burn or ache, and in some cases the protruding tissue descends into the scrotum, causing swelling and pain there as well.
Most hernias develop gradually from repeated pressure on the abdomen through heavy lifting, chronic coughing, or straining during bowel movements. A hernia that becomes trapped (incarcerated) can block the bowel and cut off blood flow to the tissue, causing severe pain and requiring emergency surgery.
Prostatitis, inflammation of the prostate gland, can also cause a deep ache in the lower abdomen or pelvis in men. It sometimes accompanies difficulty urinating, pelvic floor tension, or pain that worsens while sitting.
Inflammatory Bowel Disease
Crohn’s disease and ulcerative colitis are chronic conditions that cause inflammation in the digestive tract. Ulcerative colitis affects the colon and rectum and tends to cause lower left pain along with bloody diarrhea and urgency. Crohn’s disease can affect any part of the digestive tract but often involves the end of the small intestine, which sits in the lower right abdomen. Both conditions produce symptoms that flare and remit over months to years. Persistent cramping, weight loss, diarrhea (sometimes with blood), and fatigue are common patterns.
When Lower Abdominal Pain Is an Emergency
Most lower abdominal pain is not dangerous, but certain symptoms signal something that needs immediate attention. Go to the emergency room if you experience:
- Sudden, severe pain that came on abruptly and is getting worse
- A rigid or significantly swollen abdomen that is tender to even light touch
- Signs of shock such as rapid heart rate, lightheadedness, sweating, or confusion
- Fever with worsening pain, especially if localized to one side
- Vomiting blood or bloody stool
Pain that worsens when you gently press and then release the area (a sign of peritoneal irritation) suggests inflammation may be spreading inside the abdomen. This pattern, combined with fever or increasing pain, warrants urgent evaluation.
Acute vs. Ongoing Pain
Clinically, abdominal pain lasting fewer than seven days is considered acute. Acute pain that is severe or worsening needs prompt evaluation because conditions like appendicitis, ovarian torsion, and bowel obstruction can deteriorate quickly. Pain that has been coming and going for weeks or months points more toward chronic conditions like IBS, endometriosis, or inflammatory bowel disease, which benefit from a planned workup rather than an emergency visit.
Keeping track of when the pain occurs, what makes it better or worse, and whether it’s tied to eating, bowel movements, urination, or your menstrual cycle gives your doctor the most useful information for narrowing down the cause. Location matters too: consistent pain in the same spot suggests a structural or organ-specific problem, while pain that moves around is more typical of functional digestive issues.