A normal period lasts about four to five days, with most falling somewhere between three and seven days. Bleeding that stretches to two weeks is not typical, and it usually signals that something specific is going on, whether that’s a hormonal shift, a new contraceptive, or an underlying condition worth investigating. The good news is that most causes are treatable once identified.
How Hormones Can Keep You Bleeding
The most common reason for a period that won’t stop is a hormonal imbalance, specifically a cycle where your body didn’t release an egg (called an anovulatory cycle). In a normal month, after ovulation, your body produces progesterone. That progesterone rise and fall is what triggers the uterine lining to shed in an organized, time-limited way. Without ovulation, progesterone never kicks in properly, and the lining keeps growing thicker than usual. When it finally does start to break down, it sheds unevenly and slowly, leading to prolonged, often heavy bleeding that can easily last two weeks or longer.
Anovulatory cycles are especially common during certain life stages. If you’re in your teens and your cycles haven’t fully regulated yet, or if you’re in your late 30s or 40s approaching perimenopause, skipping ovulation occasionally is normal. Stress, significant weight changes, excessive exercise, and illness can also disrupt ovulation in any given month. A single two-week period from a missed ovulation isn’t necessarily a sign of a serious problem, but if it keeps happening, it points to a pattern worth exploring.
Conditions That Cause Prolonged Bleeding
Several medical conditions can make periods last far longer than they should. Some of the most common include:
- Polycystic ovary syndrome (PCOS): PCOS is one of the leading causes of chronic anovulation. The uterine lining builds up over weeks without the progesterone signal to shed it cleanly, resulting in heavy, prolonged episodes when bleeding finally starts. Cycles often stretch to 35 days or more apart, and the bleeding itself can last well beyond a week.
- Thyroid disorders: Your thyroid has a direct influence on your menstrual cycle. Hypothyroidism (an underactive thyroid) is strongly linked to heavy, prolonged periods. In one study of women with thyroid dysfunction, 65% of those with low thyroid hormone levels experienced heavy menstrual bleeding.
- Uterine fibroids and polyps: These are noncancerous growths in or on the uterus. They can distort the uterine lining and interfere with its ability to contract and stop bleeding efficiently. Fibroids are extremely common, particularly in women over 30.
- Adenomyosis: This occurs when tissue that normally lines the uterus grows into the muscular wall. It can cause the uterus to enlarge and bleed heavily for extended periods.
- Bleeding disorders: Between 5% and 24% of women with chronic heavy menstrual bleeding have an undiagnosed bleeding disorder, most commonly von Willebrand disease. This condition affects how well your blood clots. If you’ve always had heavy, long periods, bleed easily from cuts, or bruise frequently, a clotting disorder could be the underlying cause.
Birth Control as a Common Culprit
If you recently started, stopped, or switched a hormonal contraceptive, that alone can explain two weeks of bleeding. Breakthrough bleeding is one of the most frequent side effects of hormonal birth control, especially in the first few months.
The copper IUD deserves special mention. It contains no hormones but is well known for making periods heavier and longer. At three months after insertion, more than 70% of copper IUD users report heavier bleeding than before. Only about 8% experience lighter periods. This pattern tends to stabilize over time, but for some users, heavier and longer periods persist.
Hormonal IUDs work in the opposite direction. About two-thirds of hormonal IUD users report lighter bleeding by three months, and that trend continues at six months. However, irregular spotting and prolonged light bleeding are common in the first few months after placement. The hormonal implant follows a similar pattern: the bleeding you experience in the first three months tends to predict your ongoing pattern with the device.
If you’ve recently missed pills, taken them inconsistently, or had a new method placed, give it about three months before assuming something else is wrong. But bleeding that fills a pad every hour or two, even on a new contraceptive, warrants a call to your provider.
Signs You’re Losing Too Much Blood
Two weeks of bleeding raises a real concern about iron loss, even if the flow feels moderate. Your body uses iron to make red blood cells, and prolonged bleeding can deplete your stores faster than your diet replaces them. Iron deficiency anemia is the most common complication of heavy or prolonged periods.
The warning signs are fatigue (reported by about 80% of those with menstrual-related anemia), weakness (66%), and headaches (63%). You might also feel lightheaded, short of breath during normal activities, or notice that your skin looks paler than usual. These symptoms can creep in gradually, so you may not connect them to your period at first. If you’ve been bleeding for two weeks and feel unusually drained, those symptoms likely aren’t just from being tired.
A normal period involves losing only about two to three tablespoons of blood total. Heavy menstrual bleeding is defined as losing more than about 80 milliliters per cycle. Soaking through a pad or tampon every hour for several consecutive hours, needing to double up on pads, changing protection overnight, or passing clots the size of a quarter or larger all indicate you’re losing significantly more blood than normal.
What Testing Looks Like
If you see a provider about prolonged bleeding, expect a few standard steps. Blood work typically comes first, checking your blood count for anemia, your iron and ferritin levels (ferritin is the most reliable marker of iron stores), your thyroid function, and sometimes your hormone levels.
A transvaginal ultrasound is the first imaging test used to look for structural problems. It can identify fibroids, measure the thickness of your uterine lining, and flag anything that looks abnormal. If the ultrasound suggests polyps, fibroids inside the uterine cavity, or other structural issues, a hysteroscopy may follow. This involves a thin camera inserted through the cervix to directly visualize the inside of the uterus, and small growths can sometimes be removed during the same procedure. For women 45 and older, or when initial treatments don’t work, an endometrial biopsy is often recommended to rule out precancerous changes.
How Prolonged Bleeding Is Treated
Treatment depends entirely on the cause, which is why figuring out the “why” matters more than just stopping the bleeding. That said, several approaches can help.
For hormonal imbalances and anovulatory bleeding, the most common treatment is a course of progestin, the synthetic form of progesterone your body isn’t producing on its own. This helps the uterine lining shed completely and reset your cycle. Hormonal birth control (pills, a hormonal IUD, or other methods) can also regulate cycles long-term by keeping the lining thin and preventing excessive buildup.
For acute heavy bleeding that needs to be slowed quickly, medications that help blood clot more effectively are sometimes prescribed for a few days. These work by preventing existing clots in the uterine lining from breaking down too soon, reducing blood loss by about 30% to 50% in many cases.
If the cause is structural, like fibroids or polyps, treatment ranges from hormonal management to minimally invasive procedures to remove the growths. Thyroid disorders are treated with thyroid hormone replacement, which often resolves the menstrual irregularities as thyroid levels normalize. Bleeding disorders like von Willebrand disease have their own targeted treatments that can dramatically reduce menstrual blood loss once the diagnosis is made.
What a Two-Week Period Means for You
A single episode of prolonged bleeding, especially during a stressful month or a time of hormonal transition, may resolve on its own. But two weeks is long enough to cause meaningful blood and iron loss, and it’s a signal your body is giving you that something in the cycle went differently than it should have.
If this has happened more than once, if you’re soaking through protection every hour or two, if you’re passing large clots, or if you feel dizzy, unusually fatigued, or short of breath, those are signs the bleeding is affecting your health and not just your schedule. Tracking the length of your periods and how heavy they are gives your provider the clearest picture of what’s happening, even a simple note on your phone each day counts.