A period lasting two weeks is not normal. A typical period lasts four to five days, and anything beyond seven days is considered abnormally prolonged bleeding. If you’ve been bleeding for 14 days, something is disrupting the usual process your body uses to build up and shed the uterine lining, and several common causes can explain why.
How a Normal Period Ends (and Why Yours Hasn’t)
During a regular cycle, your body balances two hormones: estrogen and progesterone. Estrogen thickens the lining of your uterus in the first half of the cycle, then progesterone stabilizes it after ovulation. When progesterone drops, the lining sheds in an orderly way over about four to five days, with total blood loss of roughly two to three tablespoons.
When that balance breaks down, the lining can become too thick or shed unevenly. Instead of a clean, contained bleed that stops on schedule, the uterus continues to shed in patches, extending your period well past the normal window. A two-week period suggests one of several underlying causes is at play.
Hormonal Imbalance Is the Most Common Cause
The single most frequent reason for prolonged bleeding is a cycle where you didn’t ovulate. Without ovulation, your body doesn’t produce the progesterone it needs to keep the uterine lining in check. The lining keeps thickening under estrogen’s influence, then eventually breaks down irregularly, leading to heavy or prolonged bleeding that can stretch for weeks.
This type of missed ovulation (called an anovulatory cycle) happens more often than most people realize. It’s especially common during periods of significant stress, rapid weight change, intense exercise, or illness. It’s also frequent at both ends of reproductive life: in the first few years after your period starts and in the years leading up to menopause, when hormone levels fluctuate more unpredictably. If you’re in your 40s and noticing longer periods for the first time, shifting hormone levels during perimenopause are a likely explanation.
Growths in the Uterus
Structural problems inside the uterus can physically interfere with the lining’s ability to heal and stop bleeding. Two of the most common are fibroids and polyps.
Uterine polyps are small growths that form when cells in the uterine lining overgrow. They attach to the uterine wall by a base or thin stalk and can cause irregular bleeding, very heavy flow, or bleeding between periods. Fibroids are noncancerous muscle growths in or on the uterus that can distort the lining and create a larger surface area that bleeds more and longer. Both are common, often cause no symptoms at all, and are usually found during an ultrasound when someone reports prolonged or heavy bleeding.
Thyroid Problems
Your thyroid gland controls the speed of many of your body’s processes, including your menstrual cycle. An underactive thyroid (hypothyroidism) slows things down broadly, and one of its effects is heavier and longer periods. If your two-week period comes alongside fatigue, weight gain, feeling cold, or dry skin, a simple blood test can check whether your thyroid is the issue. Thyroid-related period problems typically resolve once the underlying condition is treated.
IUDs and Other Contraceptives
If you recently had a copper IUD placed, prolonged or irregular bleeding is a well-known side effect during the adjustment period. Some people report irregular bleeding for several months after insertion, though symptoms typically ease up after three to six months. Hormonal IUDs can also cause unpredictable bleeding patterns in the first few months, though they tend to make periods lighter over time rather than heavier.
Starting, stopping, or switching hormonal birth control of any kind (pills, patches, injections) can temporarily disrupt the hormonal balance that controls your cycle. A two-week bleed shortly after a change in contraception is not unusual, but it should settle within a few cycles.
Less Common but Important Causes
Bleeding disorders that affect how well your blood clots can make periods last longer and become heavier. These conditions are often present from a young age but sometimes go undiagnosed until someone seeks help for heavy periods. Infections of the cervix or uterus, certain medications (particularly blood thinners), and in rare cases, precancerous changes to the uterine lining can also cause prolonged bleeding.
Pregnancy complications are another possibility worth considering even if you don’t think you’re pregnant. Early miscarriage and ectopic pregnancy can both cause prolonged bleeding that looks like a long period but isn’t one.
What Prolonged Bleeding Does to Your Body
Two weeks of bleeding means you’re losing significantly more blood than your body expects to lose in a cycle. Normal blood loss is about two to three tablespoons total. At two weeks, you may be losing several times that amount, which depletes your iron stores over time. The result is iron-deficiency anemia, which causes fatigue, weakness, dizziness, shortness of breath, and difficulty concentrating. If you’ve been bleeding this long and feel unusually tired or lightheaded, low iron is a likely contributor. Roughly 10 to 15% of women of reproductive age deal with heavy menstrual bleeding, and iron deficiency is one of its most consistent consequences.
Signs You Need Help Quickly
Any period lasting more than seven days warrants a conversation with a healthcare provider. But certain signs mean you should be seen sooner rather than later:
- Soaking through a pad or tampon every hour for several consecutive hours
- Passing blood clots larger than a quarter
- Feeling faint, dizzy, or short of breath
- Bleeding after a positive pregnancy test
What to Expect at a Medical Visit
Evaluating a two-week period is usually straightforward. You’ll likely be asked about the timing, heaviness, and any recent changes in your life, medications, or contraception. A blood test can check for anemia, thyroid function, and pregnancy. An ultrasound of the uterus can identify fibroids or polyps. In some cases, a small tissue sample from the uterine lining helps rule out precancerous changes, particularly in women over 35 or those with risk factors.
Treatment depends entirely on the cause. Hormonal imbalances often respond to hormonal medications that regulate the cycle. Polyps can be removed in a minor procedure. Thyroid problems are managed with daily medication. For many people, the fix is simpler than they expected, but finding it requires knowing what’s behind the prolonged bleeding in the first place.