Lower abdominal pain has dozens of possible causes, ranging from mild and temporary (like gas or a pulled muscle) to conditions that need same-day medical attention (like appendicitis). Where exactly the pain is, what it feels like, and what other symptoms come with it are the best clues to narrowing down what’s going on. Here’s a breakdown of the most common reasons your lower stomach might be hurting, organized by what’s actually happening inside your body.
What’s in Your Lower Abdomen
Your lower abdomen is more crowded than most people realize. The last section of your large intestine sits in both the lower left and lower right sides. Your bladder sits low and center, just behind the pubic bone. The appendix hangs off the large intestine on the lower right. In women, the uterus, ovaries, and fallopian tubes occupy the central and lower pelvic space between the bladder and rectum. In men, the inguinal canals (passageways near the groin) and the structures connecting to the testicles run through this area.
Because so many organs are packed into a relatively small space, pain in one spot can sometimes be referred from a completely different structure. That’s why location alone isn’t always enough to pinpoint the problem.
Digestive Causes
The most common reasons for lower abdominal pain are gastrointestinal. Many of them resolve on their own, but a few need medical treatment.
Gas and Constipation
Trapped gas can cause surprisingly intense, crampy pain that moves around the lower abdomen. Constipation creates a dull, pressing ache, usually in the lower left side where stool collects before a bowel movement. Both tend to improve after passing gas or having a bowel movement, and neither comes with fever or blood in the stool.
IBS
Irritable bowel syndrome causes recurring cramping and abdominal pain along with diarrhea, constipation, or both. There’s no visible inflammation or damage to the intestines. The pain is thought to come from uncoordinated contractions in the intestinal wall and hypersensitive nerves in the gut. IBS pain often worsens after eating and improves after a bowel movement, and it tends to flare during periods of stress.
Inflammatory Bowel Disease
Unlike IBS, inflammatory bowel disease (Crohn’s disease and ulcerative colitis) involves actual inflammation in the digestive tract. The symptoms overlap with IBS, including cramping and diarrhea, but IBD also causes fevers, bloody bowel movements, and unintended weight loss. If your lower abdominal pain comes with blood in your stool or persistent diarrhea lasting more than a few weeks, IBD is worth investigating.
Diverticulitis
Small pouches called diverticula commonly form in the lower part of the colon, especially after age 50. Most people never know they have them. But when one of those pouches becomes inflamed or infected, the result is diverticulitis: significant pain in the lower left abdomen, often accompanied by fever, nausea, and sudden changes in bowel habits like new diarrhea or constipation. The pain tends to be constant rather than crampy, and it usually gets worse over hours rather than coming and going.
Urinary Tract Causes
Urinary Tract Infections
UTI pain typically centers in the lower abdomen around the pubic bone and feels like pressure or a dull stabbing sensation. The hallmark symptom is a burning feeling when you urinate, along with the urge to go frequently even when your bladder isn’t full. UTIs are far more common in women, but men can get them too, particularly with age. Cloudy or strong-smelling urine is another telltale sign.
Kidney Stones
Kidney stone pain is a different animal. It’s typically sharp, stabbing, and intense, and it tends to hit in the back or side of your lower torso rather than directly in the front of your abdomen. The pain can radiate into the groin as the stone moves down the urinary tract. You may also notice sharp pain while urinating, blood-tinged urine, or nausea. Kidney stone pain often comes in waves, with periods of severe pain followed by brief relief.
Causes Specific to Women
Pelvic and reproductive organs add a whole layer of possibilities for lower abdominal pain in women.
Menstrual Cramps and Ovulation Pain
Period cramps center in the lower abdomen and lower back and follow a predictable monthly pattern. Ovulation pain (sometimes called mittelschmerz) happens mid-cycle and usually affects one side, corresponding to whichever ovary released an egg. Both are normal, though severe menstrual pain that interferes with daily life deserves evaluation for underlying causes like endometriosis.
Endometriosis
Endometriosis causes pelvic pain or tenderness that can happen at any time, not just during your period. Periods tend to be very painful. Pain during sex, pain when urinating or having a bowel movement, back pain, bloating, and nausea are all common. Endometriomas, cysts that form on the ovaries from endometrial tissue, can add a deep, persistent ache on one or both sides.
Ovarian Cysts
Most ovarian cysts form during normal ovulation and disappear on their own within a few months. When they cause symptoms, you’ll typically feel a dull ache or fullness on one side of the lower abdomen. A cyst that ruptures causes sudden, sharp pain that can be severe but usually fades within hours to days. A cyst that twists (ovarian torsion) causes sudden, intense pain with nausea and vomiting and needs emergency treatment.
Ectopic Pregnancy
In early pregnancy, sharp pain on one side of the lower abdomen, especially with vaginal bleeding or dizziness, can signal an ectopic pregnancy, where a fertilized egg implants outside the uterus. This is a medical emergency. For any woman of reproductive age with acute lower abdominal pain, a pregnancy test is one of the first steps in evaluation.
Causes Specific to Men
Inguinal Hernia
An inguinal hernia occurs when tissue pushes through a weak spot in the abdominal wall near the groin. The classic sign is a visible bulge on one side of the pubic bone that becomes more obvious when you stand up, cough, or strain. The area may burn or ache, and pain often worsens with bending, lifting, or coughing. Large hernias can extend into the scrotum, causing pain and swelling around the testicles. If the bulge becomes painful, firm, and can’t be pushed back in, it may be incarcerated or strangulated, which needs emergency care.
Testicular Torsion
Sudden, severe pain in one testicle that radiates into the lower abdomen can indicate testicular torsion, where the testicle twists on its blood supply. This is most common in teenagers and young men, and it requires emergency surgery within hours to save the testicle.
Appendicitis: The One to Watch For
Appendicitis follows a distinctive pattern. Pain typically begins as a vague ache around the belly button, then over 6 to 24 hours migrates to the lower right abdomen, where it becomes sharper and more localized. Movement, coughing, or pressing on the area makes it worse. Nausea, vomiting, low-grade fever, and loss of appetite usually accompany the pain. If pressing on your lower right abdomen and then quickly releasing causes a spike of pain, that’s a strong indicator. Appendicitis can happen at any age but is most common between ages 10 and 30.
Signs You Need Emergency Care
Most lower abdominal pain is not an emergency, but certain combinations of symptoms indicate something serious is happening. Seek immediate care if your pain is:
- Sudden and excruciating, rather than building gradually
- Accompanied by fever, rapid heart rate, or dizziness, which can signal infection or internal bleeding
- Paired with bloody vomit, blood in your stool, or blood in your urine
- Getting worse over hours despite rest and over-the-counter pain relief
- Combined with a rigid, board-like abdomen that hurts when touched
Abrupt, excruciating abdominal pain can indicate a perforated organ, a ruptured blood vessel, or tissue losing its blood supply, all of which need urgent treatment.
How Doctors Figure Out the Cause
If you go in for evaluation, the process usually starts with a physical exam and questions about exactly where the pain is, when it started, and what makes it better or worse. Blood work and a urine sample can check for infection, inflammation, and pregnancy. For lower abdominal pain on either side, a CT scan is the recommended first imaging test because it can visualize the appendix, colon, kidneys, and other structures clearly. For women of reproductive age, a pelvic ultrasound is preferred when a gynecologic cause is suspected or a pregnancy test is positive, since it avoids radiation exposure. In some cases, doctors use ultrasound first and only move to CT if the picture is still unclear.