A period lasting two weeks is not normal. Menstrual bleeding typically lasts 2 to 7 days, and anything beyond 7 days is considered prolonged. A 14-day bleed, whether continuous or stop-and-start, signals that something is disrupting your cycle and is worth investigating.
That said, a two-week bleed doesn’t automatically mean something dangerous is happening. There are several common, treatable explanations, and understanding them can help you figure out what’s going on and what to do next.
What a Normal Period Looks Like
A normal menstrual cycle repeats every 21 to 35 days, and the bleeding portion lasts between 2 and 7 days. Total blood loss during a typical period is about 2 to 5 tablespoons. If your bleeding extends to 14 days, you’re losing significantly more blood than your body expects to, and the cause matters.
It’s also worth figuring out whether you’re experiencing one long, continuous bleed or whether your period stopped and then started again. These are different situations. A true prolonged period means continuous or near-continuous bleeding for two weeks. Bleeding that stops for several days and restarts may be breakthrough bleeding or spotting between two separate cycles, which points to different causes.
Hormonal Imbalance Is the Most Common Cause
Your uterine lining builds up each cycle under the influence of estrogen, and the hormone progesterone is responsible for keeping periods regular and signaling the lining to shed in an orderly way. When these two hormones fall out of balance, the lining can grow too thick and shed unevenly, leading to heavy or prolonged bleeding.
One of the most frequent triggers is a cycle where no egg is released. Without ovulation, your body doesn’t produce progesterone the way it normally would. The lining keeps building under estrogen’s influence, then sheds irregularly, sometimes for days longer than usual. This can happen occasionally in otherwise healthy women, especially during periods of stress, significant weight change, or illness. It’s also more common at both ends of reproductive life: in the first few years after periods begin and in the years leading up to menopause.
PCOS and Thyroid Problems
Polycystic ovary syndrome (PCOS) is one of the most common hormonal conditions affecting menstruation. It can cause periods that are very far apart, unpredictable, or, when they do arrive, unusually heavy and long-lasting. Because PCOS frequently disrupts ovulation, the uterine lining can build up over weeks or months without the normal progesterone signal to shed. When bleeding finally occurs, it can be prolonged and heavy.
Thyroid disorders, both overactive and underactive, also interfere with menstrual regularity. Your thyroid helps regulate the hormones that control your cycle, so when it’s off, your periods often are too. Both conditions are diagnosable with blood tests, and treating the underlying problem usually brings periods back to a normal pattern.
Fibroids, Polyps, and Other Structural Causes
Growths in or on the uterus are another common reason for prolonged bleeding. Uterine fibroids are noncancerous muscle growths in the wall of the uterus, and they’re extremely common, particularly in women over 30. Depending on their size and location, they can cause periods that drag on well past the normal window.
Uterine polyps are softer growths that form from an overgrowth of the uterine lining itself. They’re sensitive to estrogen, meaning they grow in response to it, and they can cause irregular bleeding, very heavy flow, or bleeding between periods. Both fibroids and polyps are typically found through an ultrasound or a procedure where a small camera is inserted into the uterus. Treatment depends on the size and severity of symptoms but ranges from medication to minor procedures to remove them.
Birth Control Can Cause Extended Bleeding
If you recently started a new form of hormonal birth control, extended bleeding or spotting is a well-known side effect. This happens more often with low-dose pills, hormonal IUDs, and the implant. With IUDs, irregular bleeding and spotting in the first few months after placement is common and usually improves within 2 to 6 months. With the implant, the bleeding pattern you experience in the first three months tends to be your pattern going forward.
Copper (non-hormonal) IUDs can also make periods heavier and longer, particularly in the first several months. If you’ve had a new contraceptive placed in the last few months and are now experiencing a two-week bleed, this is likely a factor, but it’s still worth confirming with your provider, especially if the bleeding is heavy.
Why Prolonged Bleeding Matters
Beyond the inconvenience, two weeks of menstrual bleeding puts you at real risk for iron-deficiency anemia. Your body uses iron to make red blood cells, and losing more blood than normal depletes those stores. Symptoms of anemia include fatigue, weakness, pale skin, shortness of breath, and feeling cold. If you’ve been bleeding for extended periods (no pun intended) over multiple cycles, you may already be iron-deficient without realizing it, since the symptoms creep up gradually.
Signs that your bleeding needs prompt attention include soaking through a pad or tampon every hour for several consecutive hours, passing blood clots the size of a quarter or larger, needing to double up on pads, or waking up at night to change protection. These point to blood loss that your body may not be keeping up with.
What to Expect at a Doctor’s Visit
If you’re experiencing a two-week period, especially if it’s happened more than once, a provider will typically start by asking about your menstrual history. You may be asked to keep a diary tracking which days you bleed, how heavy the flow is, and how many pads or tampons you use. This information helps distinguish between a single long period and irregular bleeding between cycles.
From there, common next steps include blood tests to check for anemia, thyroid problems, and clotting disorders. An ultrasound of the uterus and ovaries can reveal fibroids or polyps. If the ultrasound is inconclusive, a more detailed imaging test may be done where fluid is injected into the uterus to get a clearer picture of the lining. In some cases, a small tissue sample from the uterine lining is taken and examined to rule out precancerous changes, particularly in women over 40 or those with risk factors.
Most causes of a two-week period are treatable once identified. Hormonal imbalances can often be managed with hormonal therapy that restores progesterone levels. Fibroids and polyps may be removed through minimally invasive procedures. The key is identifying the specific cause rather than assuming it will resolve on its own, because in many cases, prolonged bleeding recurs cycle after cycle until the underlying issue is addressed.