Blood in your stool is usually caused by something common and treatable, most often hemorrhoids or a small tear near the anus. But the color, amount, and pattern of bleeding all matter, and some causes are unique to women or more likely during certain life stages like pregnancy and menstruation. Understanding what different types of bleeding look like can help you figure out what’s going on and whether you need prompt medical attention.
What the Color of the Blood Tells You
The color of blood in or on your stool is a useful clue about where the bleeding is coming from. Bright red blood typically originates lower in the digestive tract, near the rectum or anus. This is the most common type women notice on toilet paper or in the bowl, and it usually points to hemorrhoids, a fissure, or another issue close to the surface.
Black, tarry stools signal something different. Blood that starts higher up in the digestive tract, such as in the stomach or upper intestine, gets broken down by digestive enzymes as it travels through. By the time it reaches the stool, the blood has turned dark and sticky. This type of bleeding is less common but more likely to reflect a serious issue like an ulcer or upper GI bleed and warrants a prompt call to your doctor.
Hemorrhoids: The Most Common Cause
Hemorrhoids are swollen veins in or around the rectum, and they’re the single most common reason for blood in the stool. They develop when pressure builds in the veins of the lower rectum, often from straining during bowel movements, sitting for long periods, or chronic constipation. The bleeding is typically bright red, painless, and shows up on the toilet paper or drips into the bowl.
Internal hemorrhoids that have pushed outside the anus tend to feel soft, smooth, and almost rubbery. External hemorrhoids can feel like a small grape or marble sitting just outside the opening. Neither type is dangerous on its own, though they can be uncomfortable and sometimes itchy. Most hemorrhoids resolve with increased fiber, hydration, and over-the-counter treatments within a few days to a couple of weeks.
Anal Fissures
An anal fissure is a small tear in the lining of the anal canal. Like hemorrhoids, fissures often happen after straining to pass a hard stool. The key difference is pain: fissures typically cause a sharp, stinging sensation during and after a bowel movement, along with bright red blood. They’re especially common during and after pregnancy, when constipation is frequent. Most fissures heal on their own within a few weeks with stool softeners and warm baths.
Why Pregnancy and Postpartum Bleeding Is So Common
If you’re pregnant or recently gave birth, rectal bleeding is extremely common, and hemorrhoids are almost always the reason. As the uterus expands, it presses on the pelvic veins and the large vein that carries blood from your lower body. This slows circulation and increases pressure on the veins beneath the uterus, causing them to swell.
Progesterone makes the problem worse in two ways. It relaxes blood vessel walls, making veins more prone to swelling, and it slows intestinal movement, which leads to constipation. The harder you strain on the toilet, the more pressure those already-stressed veins absorb. Many women also develop hemorrhoids during the pushing phase of labor itself. Postpartum hemorrhoids usually improve within weeks as hormone levels normalize, though staying on top of fiber and hydration speeds recovery.
Endometriosis and Cyclical Bleeding
One cause of rectal bleeding that’s specific to women is bowel endometriosis. When endometrial-like tissue grows on or into the wall of the intestine, it can cause bleeding from the rectum that follows a predictable pattern: symptoms tend to be worst in the days before a period and during menstruation, then ease up afterward. If you notice rectal bleeding that consistently lines up with your menstrual cycle, this is worth raising with your doctor. That said, hemorrhoids and other common bowel conditions remain a more frequent explanation even when the timing seems cyclical, so a proper evaluation is important before jumping to conclusions.
Inflammatory Bowel Disease
Ulcerative colitis and Crohn’s disease both cause chronic inflammation in the digestive tract and can produce blood in the stool. Ulcerative colitis typically starts in the rectum and spreads through part or all of the large intestine, causing ulcers that bleed. Crohn’s disease can affect any part of the GI tract but most commonly develops in the small intestine and the upper portion of the large intestine.
Alongside bloody stool, both conditions tend to cause lower abdominal pain or cramping, fatigue, unintended weight loss, and urgent or frequent bowel movements. These symptoms come and go in flares rather than appearing once and disappearing. If you’re experiencing a combination of these, particularly ongoing fatigue and weight loss alongside bloody stools, it points toward something beyond a simple hemorrhoid.
When Bleeding Could Signal Cancer
Colorectal cancer is a less common but serious cause of blood in the stool. The U.S. Preventive Services Task Force now recommends routine screening starting at age 45 for average-risk adults, lowered from the previous starting age of 50, reflecting rising rates in younger people. But symptoms can appear at any age.
The warning signs that set colorectal cancer apart from hemorrhoids include a persistent change in bowel habits (new diarrhea or constipation that doesn’t resolve), ongoing abdominal cramping or gas, a feeling that your bowel doesn’t fully empty, unexplained weight loss, and progressive weakness or tiredness. Iron deficiency anemia in a woman who isn’t menstruating heavily can also be a red flag, since slow, chronic bleeding from a tumor can drain iron stores over months without producing visible blood.
A hard, irregular, or rough lump near the anus that bleeds is also different from a hemorrhoid and could indicate anal cancer. If any symptoms last more than two weeks, get worse, or go away and then return in a short period, get them evaluated. Hemorrhoid bleeding is typically intermittent and directly tied to straining; cancer-related bleeding tends to be more persistent and accompanied by other changes in how your body feels.
How the Cause Is Identified
Your doctor will start with a conversation about the color, frequency, and pattern of bleeding, along with any other symptoms. A physical exam usually includes a digital rectal exam, where a gloved finger checks for internal hemorrhoids, fissures, or abnormal masses. This is quick and only mildly uncomfortable.
If the cause isn’t obvious from the exam, the next step is often an anoscopy, a brief in-office procedure where a small lubricated tube (roughly finger-sized) is inserted to give a direct view of the anal canal. For bleeding that could be coming from higher in the colon, or for anyone with risk factors for colorectal cancer, a colonoscopy provides a complete look at the entire large intestine. Your doctor may also order a stool test that checks for hidden blood not visible to the eye, which is one of the standard screening tools for colorectal cancer in adults 45 and older.
Signs That Require Emergency Care
Most rectal bleeding doesn’t require a trip to the emergency room, but some situations do. Heavy or continuous bleeding that doesn’t stop, or bleeding paired with severe abdominal pain or cramping, warrants immediate medical attention.
Call 911 if you’re experiencing significant rectal bleeding along with any signs of shock: rapid, shallow breathing, dizziness or lightheadedness when you stand, blurred vision, fainting, confusion, nausea, cold or clammy skin, or very low urine output. These signs mean your body is losing blood faster than it can compensate, and you need emergency intervention.