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Menstruation can feel like the least-fun guessing game ever. When is Aunt Flo coming? Why is she late? Why is she early? Why has she brought so many friends? And, perhaps most frustrating: When is she leaving?

But no matter how many times you tell her "You're drunk, go home," the menstrual matriarch is going to stick around as long as she darn well pleases.

So how do you know when she's overstayed her visit? While it can feel like anything more than a day or two bleeding is too long, the average period lasts anywhere from two to seven days, according to the Mayo Clinic.

But there's "normal" and then there's yournormal. If your period is a a day or two more or less than this range and you don't have any other problems, you probably don't need to be concerned. However, a period that lasts 10 days or more, or suddenly changes significantly in length, for three or more cycles in a row, warrants a call to your doctor, says Tom Toth, M.D., a reproductive endocrinologist at Boston IVF, as that can be a sign something is wrong.

Think of your period like the canary in the coal mine—often it's one of the first signs that trouble is brewing is your reproductive system or even overall health and you should take it seriously. When it comes to long periods, there are some common causes.

Here, we break them down for you, what they may mean, and what you should do next.

With either IUD, if the prolonged periods don't settle down after three cycles, it's time to go back to your doctor, as it's possible the IUD moved out of position or simply doesn't play nice with your body.

It turns out that both can cause abnormally long bleeding, especially right after insertion, Toth says. Longer, heavier periods are a known side effect of the copper IUD. The progestin IUD, however, is often marketed to women as a way to reduce or even eliminate their periods. And while it typically does have that effect over time, the first few cycles may have more or longer bleeding than usual, he says.

One of the most common causes of long periods in younger women are intrauterine devices, a type of birth control placed directly into your cervix. There are two main types: a non-hormonal, copper-based IUD (like Paraguard), and a hormonal, progestin-based IUD (like Mirena and Skyla).

Wait just a second: Isn't the tell-tale sign of pregnancy no periods? Yes, but not all the time, Toth says. "A common cause for abnormal menses, including longer bleeding, is pregnancy," he explains, adding that typical symptoms of pregnancy, like nausea, may be absent." Any time a woman has unusual bleeding, it's always best to eliminate possibility of pregnancy with a blood test for pregnancy for reassurance," he says.


"Uterine abnormalities, such as polyps or fibroids, can cause prolonged periods because they distort the endometrial cavity which can lead to increased blood flow," Toth explains. They may sound scary but don't panic. Polyps and fibroids are incredibly common—70 to 90 percent of women will have at least one before they're 50—and on their own they don't indicate a more serious disease, like cancer.

These benign growths often don't have any symptoms and if they do, it's usually prolonged periods. Most likely your doc will just recommend keeping an eye on them, but if they cause pain or grow very large they can be surgically removed.


Early miscarriages are much more common than you may realize. Up to half of all pregnancies end in miscarriage, often before the woman even realizes she was pregnant, according to the March of Dimes.

The only sign? An extra heavy or long period. Your menstrual cycle length should return to normal within one to two cycles—if it stays abnormally long after three cycles, call your doctor, Toth says. About one in 100 women suffer from repeat miscarriages, so it's important to rule this out as a cause of frequent, prolonged periods.

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Polycystic ovary syndrome affects about 10 percent of women of childbearing age. It's named for the cysts that grow on the ovaries, preventing eggs from maturing, and often making the woman infertile. PCOS also wreaks havoc on hormone levels, causing weight gain, excess hair growth, and, yes, prolonged periods, Toth says. You'd think that not ovulating would give you a free pass on bleeding, but the opposite is often true, he adds—no egg means long, wacky cycles.

If you're experiencing any of these symptoms of PCOS, talk to your doctor about getting tested.



Anything that manipulates your hormones has the potential to make your periods longer, Toth says. This includes all types of hormonal birth control like the pill, patches, rings, shots, and implants. The good news is that there are lots of options with varying levels and types of hormones so if your body doesn't respond well to one type or dosage, there's a good chance you can find a different one that will work.

The length of your period is just one factor your doctor will use to help you determine which type of birth control works best for you. (And if your body just hates all hormonal birth control, there are several non-hormonal options as well.)


It's rare but it's possible that extra-long periods are a sign of an underlying illness, like a hematologic (blood) disease or cancer, Toth says. In fact, abnormal vaginal bleeding—such as bleeding after vaginal sex, bleeding and spotting between periods, and having periods that are longer or heavier than usual—is one of the first, and sometimes the only, early sign of cervical cancer, according to the American Cancer Society.

Make sure you stay up on all your Pap smears and HPV tests, tell your doctor about your family history of female cancers, and call your doctor right away if you experience any of these symptoms.


Oh yes, simply getting older can mess with your period. Menopause, which technically means you've gone 12 or more months without a period, hits women around age 50. However, your body starts the natural decline in hormones that leads up to menopause as early as 35, says Christiane Northrup, M.D., author of Women’s Bodies, Women’s Wisdom. You may notice your periods getting longer or shorter, your cycle becoming more random, and other slight changes in your menstruation.

If you've ruled out everything else, and you're in your mid- to late- thirties, your prolonged periods might simply be due to the natural process of aging. There is, however, such a thing as early menopause, which can affect women even in their twenties, so talk to your doctor if this runs in your family or if you're showing other signs of menopause.


AuthorBonjour Jolie