Pain in the lower part of your abdomen usually comes from your intestines, since your small and large intestines take up most of the space in that area. The most common reasons are everyday digestive issues like gas, constipation, and indigestion. But depending on where exactly the pain is, how it started, and what other symptoms you have, it can also point to something in your bladder, reproductive organs, or appendix.
Where the pain sits and how it behaves are the two biggest clues to what’s going on. Here’s a breakdown of the most likely causes, organized by what the pain actually feels like.
Gas, Constipation, and Indigestion
These are by far the most frequent reasons for lower abdominal pain, and they tend to come and go. Gas pain can feel sharp and crampy, often shifting from one spot to another as air moves through your intestines. Constipation usually produces a dull, bloated pressure in the lower left side, since that’s where your colon makes its final turn before the rectum. Indigestion can cause a more generalized ache across the lower belly.
You’ll usually know this is the culprit if the pain eases after a bowel movement or after passing gas, if your diet recently changed, or if you’re dehydrated. These causes resolve on their own within hours to a couple of days. If constipation lingers beyond a week or becomes a recurring pattern, it’s worth looking into what’s driving it.
Pain on the Lower Right Side
Right-sided lower abdominal pain gets more attention because of appendicitis. The classic pattern starts as a vague ache around your belly button, then over 12 to 24 hours migrates down to the lower right. The pain sharpens, and it hurts more when you move, cough, or press on the area and release. Fever, nausea, and loss of appetite often follow. Appendicitis requires surgery, and it can become dangerous within a day or two if the appendix ruptures.
Not every right-sided pain is appendicitis, though. Swollen lymph nodes in the tissue that connects your intestines to your abdominal wall (a condition called mesenteric lymphadenitis) can mimic appendicitis closely. It’s more common in children and young adults and often follows a viral infection like a cold or stomach bug. The key difference is that it clears up on its own without treatment.
Pain on the Lower Left Side
Diverticulitis is the standout cause of lower left abdominal pain, especially if you’re over 40. Small pouches that form along the wall of your colon can become inflamed or infected, producing pain that’s usually sudden and intense, though it can also start mild and build over several hours. Fever, nausea, and a change in bowel habits (sudden diarrhea or constipation) typically come along with it. The tenderness is localized enough that pressing on the lower left side of your belly will reproduce the pain.
Mild diverticulitis sometimes resolves with rest, a temporary liquid diet, and antibiotics. More severe cases can require hospitalization. If you’ve had one episode, you’re at higher risk for another.
Bladder Infections
If the pain sits low and centered, right behind your pubic bone, your bladder may be involved. Bladder infections cause a dull pressure or discomfort in the lower abdomen along with burning during urination, frequent urges to go (even when little comes out), and urine that looks cloudy, smells strong, or contains blood. Women get bladder infections far more often than men because of a shorter urethra, but men can develop them too, particularly later in life.
A simple urine test confirms the diagnosis, and a short course of antibiotics typically resolves symptoms within a day or two. Untreated bladder infections can travel to the kidneys, where they become more serious. Kidney pain usually shows up in the back or flank but can wrap around to the front of your lower abdomen.
Reproductive Causes in Women
For women, several pelvic conditions cause pain that feels like it’s coming from the lower belly. Menstrual cramps and ovulation pain (a brief, sharp twinge on one side mid-cycle) are the most common and usually harmless. Ovarian cysts can produce a deeper, one-sided ache that comes on gradually.
Pelvic inflammatory disease (PID) is a more serious possibility. It develops when a sexually transmitted infection spreads to the uterus or fallopian tubes, and its symptoms are often subtle enough to be mistaken for general abdominal discomfort. Lower abdominal pain paired with unusual vaginal discharge, pain during sex, or abnormal bleeding between periods raises the concern. PID sometimes causes a fever above 101°F. Because it can lead to long-term fertility problems, early treatment matters. Many women with PID have mild or nonspecific symptoms, so it often goes undiagnosed unless a clinician specifically checks for it.
Hernias
An inguinal hernia happens when tissue (usually a loop of intestine) pushes through a weak spot in your lower abdominal wall near the groin. You might notice a visible bulge on one side of your pubic bone that becomes more obvious when you stand up, cough, or strain. It produces a burning or aching sensation at the bulge, along with pressure in the groin that worsens with bending or lifting. In men, a large hernia can extend into the scrotum and cause pain and swelling there. Hernias don’t resolve on their own and typically need surgical repair, though the timing depends on how much they bother you and whether the tissue gets trapped.
Irritable Bowel Syndrome
If your lower abdominal pain keeps coming back over months without a clear cause, irritable bowel syndrome (IBS) is a common explanation. The diagnostic threshold is recurrent abdominal pain at least one day per week for the past three months, with symptoms that started at least six months before that. The pain is linked to bowel movements: it may get better or worse after going, and it’s usually accompanied by changes in how often you go or what your stool looks like.
IBS doesn’t cause visible damage to your intestines, and it doesn’t raise your risk of cancer or other serious diseases. But it can significantly affect your daily life. Dietary changes, stress management, and certain medications can help control symptoms, and tracking which foods trigger flare-ups is one of the most useful things you can do on your own.
How Location Helps Narrow It Down
- Lower right: appendicitis, swollen lymph nodes, ovarian cyst (women)
- Lower left: diverticulitis, constipation, ovarian cyst (women)
- Center/behind pubic bone: bladder infection, menstrual cramps, PID
- Near the groin: inguinal hernia, kidney stone that has traveled to the lower ureter
- Diffuse or shifting: gas, IBS, gastroenteritis
Signs That Need Prompt Attention
Most lower abdominal pain is temporary and resolves without treatment. But certain combinations of symptoms signal something that needs medical evaluation sooner rather than later.
Pain paired with a fever suggests inflammation or infection, such as appendicitis, diverticulitis, or a pelvic infection. Pain with blood in your stool can indicate anything from hemorrhoids to ulcers to colorectal cancer, and it warrants investigation regardless of severity. Pain with yellowing of your skin or eyes points toward a liver or gallbladder problem. And any abdominal pain that is severe, that steadily worsens over hours, or that prevents you from standing or walking comfortably is worth getting checked out the same day.
If your doctor needs imaging to figure out what’s going on, a CT scan is the preferred first test for lower abdominal pain on either side. For pregnant patients, ultrasound or MRI is used instead to avoid radiation exposure.