Lower abdominal pain has dozens of possible causes, ranging from trapped gas that resolves in hours to conditions that need prompt medical attention. The location, timing, and quality of the pain all help narrow down what’s going on. Here’s a practical guide to the most common reasons your lower stomach might be hurting and what to watch for.
Common Digestive Causes
The most frequent culprits behind lower abdominal pain are everyday digestive issues: gas, constipation, indigestion, and mild diarrhea. These tend to cause cramping that comes and goes, often improves after a bowel movement or passing gas, and doesn’t wake you from sleep. If your pain fits that pattern, it’s likely nothing serious.
When the pain persists or recurs over weeks and months, irritable bowel syndrome (IBS) becomes a strong possibility. IBS is formally diagnosed when you’ve had abdominal pain at least one day per week for three months, and the pain is tied to changes in how often you go, what your stool looks like, or whether you feel better or worse after a bowel movement. It’s one of the most common gastrointestinal conditions, and while it can be genuinely disruptive, it isn’t dangerous.
Inflammatory bowel diseases like Crohn’s disease and ulcerative colitis cause deeper, more persistent pain, often with bloody stool, weight loss, or fatigue. These are less common than IBS but worth considering if your symptoms are severe or worsening over time.
Right Side Pain: Appendicitis
Appendicitis follows a distinctive pattern. The pain typically starts around your belly button as a vague ache that comes and goes. Over several hours, nausea and sometimes vomiting develop. Then the nausea fades and the pain migrates to your lower right abdomen, becoming sharper and more constant. The most tender spot sits about two inches along a line drawn from your hip bone toward your belly button.
This migration from the center to the lower right is the hallmark of appendicitis. If you’re experiencing that progression, especially if walking or pressing on the area makes it worse, get evaluated quickly. An inflamed appendix can rupture, and the timeline from first symptoms to rupture is typically 24 to 72 hours.
Left Side Pain: Diverticulitis
Pain concentrated in the lower left abdomen, particularly in adults over 40, often points to diverticulitis. This happens when small pouches that form in the colon wall become inflamed or infected. The pain is usually steady rather than crampy, and it may come with fever, nausea, or a change in bowel habits.
Mild cases are typically managed with rest, a temporary shift to easily digestible foods, and sometimes antibiotics. Severe cases, especially those with high fever or signs of complications, usually require hospital treatment.
Urinary Tract Infections and Kidney Stones
A bladder infection can cause a dull pressure or discomfort in the lower abdomen that’s easy to mistake for a digestive problem. The key difference is what else comes with it: burning during urination, frequent urgent trips to the bathroom even when your bladder is nearly empty, and urine that looks cloudy, pink, or smells unusually strong. If you’re having those urinary symptoms alongside lower abdominal pressure, a UTI is the most likely explanation.
Kidney stones cause a different kind of pain. It’s usually intense and comes in waves, often radiating from the back or flank down toward the groin on one side. Some people describe it as the worst pain they’ve ever felt. If the stone is small, it may pass on its own over days to weeks. Larger stones sometimes need medical intervention to break up or remove.
Causes Specific to Women
The reproductive organs sit right in the lower abdomen, which means several gynecological conditions can produce pain that feels like a stomach issue.
Ovulation pain (sometimes called mittelschmerz) hits roughly two weeks before your period and causes a sharp twinge or dull ache on one side of your lower abdomen. It’s harmless and usually lasts a few hours to a day or two. Ovarian cysts can cause similar one-sided pain, sometimes with bloating or a feeling of fullness. Most cysts resolve on their own within a cycle or two, but large or ruptured cysts can cause sudden, severe pain.
Endometriosis causes chronic pelvic pain that tends to flare around your period but can occur at any time. The pain often worsens over months or years and may come with heavy periods, pain during sex, or difficulty getting pregnant.
Pelvic inflammatory disease (PID) is an infection of the reproductive organs, usually related to sexually transmitted bacteria. It often produces subtle or easy-to-miss symptoms: mild lower abdominal pain, unusual vaginal discharge, pain during sex, or irregular bleeding. Many cases go unrecognized because the symptoms seem minor, but untreated PID can cause long-term complications including fertility problems.
Ectopic pregnancy is a time-sensitive emergency. If you could be pregnant and you’re experiencing pelvic pain with light vaginal bleeding, get evaluated immediately. The first warning signs are often mild, but as the pregnancy grows outside the uterus (usually in a fallopian tube), the tube can rupture and cause life-threatening internal bleeding. Signs of rupture include sudden severe pain, extreme dizziness, fainting, or shoulder pain.
Causes Specific to Men
Inguinal hernias are one of the more common causes of lower abdominal pain in men. You may notice a bulge on one side of your pubic bone that becomes more obvious when you stand up, cough, or strain. The area often feels like it’s burning or aching, and the discomfort gets worse when you bend over, lift something heavy, or cough. Sometimes the hernia extends into the scrotum, causing pain and swelling around the testicle. Hernias don’t heal on their own and generally require surgical repair, though the timing depends on how symptomatic they are.
When the Pain Needs Emergency Care
Most lower abdominal pain is not an emergency. But certain features signal that something serious may be happening and you should head to an emergency room rather than waiting it out:
- Severe pain that makes it hard to move, eat, or drink
- Sudden onset of intense pain rather than a gradual build
- High fever alongside abdominal pain
- Blood in your stool or vomit
- Abdominal pain after trauma such as a fall, car accident, or blow to the stomach
Pain that starts around your belly button and migrates to the lower right over several hours also warrants prompt evaluation for appendicitis.
How Doctors Figure Out the Cause
If your pain is persistent or concerning enough to seek care, doctors narrow things down based on where exactly it hurts, how it started, and what other symptoms you have. They’ll typically ask about your bowel and urinary habits, menstrual history if relevant, sexual history, and whether the pain changes with eating, movement, or position.
Imaging is often the next step. Ultrasound is the first choice for women of reproductive age with pelvic pain because it’s excellent at identifying ovarian cysts, ectopic pregnancies, and PID without any radiation exposure. It can also evaluate the appendix and urinary tract in both men and women, though its accuracy for appendicitis depends on the operator’s skill, with studies showing it catches about 78% of cases. CT scans provide a more detailed look and are commonly used when appendicitis, diverticulitis, or kidney stones are suspected and ultrasound hasn’t given a clear answer. A urine test can quickly confirm or rule out a urinary tract infection.
For chronic or recurring pain, the diagnostic path often includes blood work, stool tests, and sometimes a colonoscopy or other specialized testing depending on the pattern of symptoms and your age.