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There’s nothing comfortable about bleeding from your vagina for days on end. So when your period decides to stick around for a few extra days, you notice.

Here’s the thing: your version of a “normal” period is going to be a little different than your squad’s, your sister’s, and even your mom’s.

A “typical” period stops 2 to 7 days after it starts. But if yours has been overstaying its welcome for many cycles now, it might be time to think about why.

Here are 16 reasons why your period just can’t stop, won’t stop.

While not an actual period, spotting in the early days of pregnancy is totally normal. In fact, sometimes bleeding comes before any other symptoms (read: nausea) kick in.

Bottom line: if you think you’re pregnant, take a test.

Sadly, about 10 to 15 percent of pregnancies end early, and bleeding could be a sign of early miscarriage.

Heavy or abnormal bleeding plus pelvic pain during pregnancy could also be a sign of an ectopic pregnancy, a pregnancy that forms outside of your uterus. This is a life-threatening situation.

If you’re pregnant and bleeding, call your OB/GYN as soon as you can. They can detect both regular and ectopic pregnancies with an ultrasound and a blood test, and help determine if you’ve had a miscarriage.

Ovulation bleeding affects 3 percent of women. But we’re not talking a full-blown period here — think light spotting.

Ovulation usually occurs in the middle of your cycle (anywhere from 11 to 21 days after your period), but believe it or not, your Fertile Myrtle days can vary month to month.

If you ovulate toward the end of your cycle and start to bleed, it can feel like the period that never ends.

Ovulation bleeding can be triggered by hormonal shifts and irregular ovulation, but in most situations it’s NBD. Still curious about ovulation bleeding? Keep reading.

Heavy, irregular periods are hallmark side effects of intrauterine devices (IUDs), a type of birth control implanted directly into your uterus. Whether you went hormonal or nonhormonal, both can knock your period out of whack.

Other typical post-IUD symptoms:

  • implantation pain
  • cramping or backaches
  • spotting between periods
  • worsened cramps (rude)

The good news: you should get relief from your mega periods (plus any other post-IUD symptoms) within 3 to 6 months. Any longer than that, you should go back to your doc.

Birth control is meant to mess with your hormones. And even if you’re popping the pill (or slapping the patch, or… using the ring) to make your periods shorter or more regular, you might end up with longer, heavier periods.

This is pretty common while your body is adjusting to a new hormonal birth control med. But if it lasts more than a few months or is killing your vibe, go see your doc — they might switch your brand.

For something so small, your thyroid (that little butterfly-shaped gland at the base of your neck) affects SO many things, including (you guessed it) your menstrual cycle.

So, when your thyroid produces too many or too few hormones, it can make your periods heavy, irregular, or go away completely.

Long, heavy periods are a symptom of hypothyroidism, or underactive thyroid. It’s more likely to develop in women after menopause, but one in eight women will develop some form of thyroid issue at any age.

Other symptoms of hypothyroidism include:

  • feeling cold when other people do not
  • constipation
  • weight gain
  • feeling very tired
  • pale, dry skin
  • dry, thinning hair

See your doc for a quick blood test. They’ll test your hormone levels and, if you’re out of whack, prescribe a daily pill.

It happens when the tissue that lines your uterus grows inside your uterine walls where it doesn’t belong. The uterine walls thicken, causing long, heavy, and painful periods.

Adenomyosis can also come with:

  • pelvic pain before your period
  • heavy feeling in your pelvis
  • pain with sex
  • pain with bowel movements

With such broad symptoms, it’s no surprise it can take years to nail down a diagnosis. Plus, a third of women with adenomyosis don’t even have symptoms ¯\_(ツ)_/¯.

Treatment options range from doing nothing (especially if you’re trying to get pregnant), to hormonal and nonhormonal meds, and hysterectomy.

Fibroids and polyps are two types of uterine growths that can cause periods from hell. Both are rarely cancerous, but can seriously affect your fertility and your quality of life during your period. Here’s the breakdown:

Uterine fibroids are noncancerous growths made of your uterine muscle tissue. They’re surprisingly common — 80 percent of women will have at least one by age 50, and they run the gamut in size and shape.

Fibroids can cause:

  • painful, heavy bleeding
  • a full feeling or swollen lower stomach
  • a gotta-pee-all-the-time feeling
  • pain with sex
  • lower back pain
  • fertility challenges

Your OB/GYN might do an ultrasound, MRI, x-ray, or dye test to check for fibroids. Common treatment options include birth control pills, IUDs, hormonal treatments, and surgery.

Uterine polyps are small, usually noncancerous growths that grow from your uterine lining and attach to the uterine wall. They’re pretty common, and you could have more than one.

Some women have no symptoms at all, but classic symptoms include:

  • bleeding between periods
  • heavy periods
  • bleeding in unpredictable frequencies and amounts during your period

If polyps are causing symptoms and it’s affecting your day to day, surgery is the main course of action here. But beware: they can return.

Polycystic ovary syndrome (PCOS) causes cysts to grow on your ovaries which keep your eggs from maturing, releasing, and doing their thing.

If you’re thinking no egg=no bleeding? Think again — this condition can send your hormones on an uncharted course. PCOS is one of the most common (but treatable!) causes of infertility.

Telltale signs:

  • irregular, prolonged periods — coming too often or not often enough
  • hair growth on your face and chin
  • acne
  • thinning hair
  • weight gain or difficulty losing weight
  • skin tags
  • trouble getting pregnant (from the whole no ovulating issue)

The exact cause of PCOS is unknown, but experts believe high levels of androgens and insulin are to blame. If you have PCOS, you might be prescribed birth control, or encouraged to lose weight.

We already talked about birth control pills, but did you know other meds could also stretch out your period? Anti-inflammatories, aspirin, and blood thinners can contribute to heavier, longer bleeding.

Stress causes a rise in cortisol, which can affect the production and interaction of hormonal players in your menstrual cycle.

Before you panic about your period, think about your stress levels. If you’re going through some heavy stuff, this could be the cause.

Endometriosis (casually referred to as “endo”) happens when tissue that’s similar to the kind that lines your uterus grows elsewhere.

Because it’s so similar to your uterus, that rogue tissue swells and bleeds in response to your cycle. The result, more often than not: long, painful, heavy periods.

Some women don’t experience symptoms, while for others this condition is unbearable. Other symptoms include:

  • painful menstruation
  • chronic back and pelvic pain
  • painful sex
  • bleeding between periods
  • painful 💩
  • nausea, constipation, and bloating
  • fertility challenges

Treatments depend on the severity of the case, plus where you’re at on your fertility journey. Birth control, hormonal meds, and surgery are all on the table.

The best way to find out if endo is stretching out your periods is to talk to your gyno.

Turns out having obesity encourages Aunt Flo to extend her stay by promoting estrogen production.

Extra estrogen can mess with your cycle, including missed, irregular, or (you guessed it) long, heavy periods. In the case of a period that just won’t quit, excess estrogen can cause your uterine lining to thicken, resulting in a monthly mess.

If you’re trying to lose weight, be careful not to overcorrect — losing too much weight too fast can cause your period to ghost.

Pelvic inflammatory disease (PID), is a bacterial infection of your lady parts. It’s usually caused by bacteria from sexually transmitted infections (STIs) like gonorrhea and chlamydia.

Irregular, abnormal-for-you periods, and spotting between periods are classic symptoms of PID, which might be why your periods are hanging on.

Some women don’t have symptoms, but untreated PID could lead to fertility challenges and chronic pelvic pain.

Other symptoms:

  • abdominal pain (the most common)
  • bleeding during sex
  • pain when you pee
  • unusual discharge
  • foul odor down there
  • fever

PID is usually treated with antibiotics.

If your period has strayed from your unique “normal,” it could be an early sign of cervical or uterine cancer.

These cancers can cause changes in the length or heaviness of your period, make you bleed between periods and after sex, and can even cause bleeding after menopause.

Your yearly pap smear and HPV test, are the best (and really, only) way to screen for, prevent, or catch cervical cancer early. But there’s no screening for uterine cancer, so it’s more important than ever to report changes and weirdness to your doc.

And, as always, keep your doc in the loop about your family history of reproductive cancers.

Menopause (usually) rears its head around age 50, but perimenopause, or the time leading up to menopause, when symptoms may begin, can start as early as age 35.

During perimenopause, your regular estrogen/progesterone pattern can start to wax and wane.

Your period might be longer and heavier for a few months, and shorter and lighter the next. The number of days between periods may increase or decrease, and you might even begin to skip periods.

Think you might be entering perimenopause? Talk to your doc.

A good rule to follow when it comes to your period: if you see something out of the ordinary for you, say something. It’s not the easiest call to make, but getting answers sooner than later will ease your mind and prevent any underlying issues from getting worse.

Reach out to your doc right away if you experience:

  • really heavy bleeding that soaks through one or more tampons or pads every hour
  • longer periods for three or more cycles
  • periods within less than 3 weeks of each other
  • bleeding after sex or between periods
  • vomiting, nausea, fever, or severe pain during periods

Buckle up, babe. Since there are so many explanations, your doc will likely ask about:

  • when your period started
  • how many pads and tampons you use in a day
  • sexual activity
  • other symptoms
  • medical history, including your fam’s

They may do a pelvic exam on the spot and take your vital signs, too.

Your doc may also recommend some testing:

  • blood tests (to check hormone levels)
  • pap smear
  • biopsy
  • abdominal or transvaginal ultrasound

It sounds like a non-answer, but trust: treatment for long periods really depends on the underlying cause.

Hormonal birth control is a go-to for period problems, especially if wonky hormone levels are to blame for extended periods of bleeding. They can lighten up your flow, get you back on a regular schedule, or even stop them completely.

If your long periods are also crazy-heavy (the technical term is menorrhagia), your doc might be concerned about your risk for anemia, or iron deficiency.

Anemia can leave you feeling weak and tired, so your doc might put you on a regimen of iron supplements and ibuprofen, which actually can reduce the amount of bleeding each month.

Surgery is an option, too. A procedure called dilation and curettage might be called in to thin the layer of your uterus and help reduce bleeding. If you’re not on the baby train, endometrial ablation, resection, or even a full-on hysterectomy can relieve your long periods (but they will affect your fertility).

Don’t panic. There are SO many reasons your period is overstaying its welcome. Longer-than-usual periods could be a fluke, but they may also be a sign of an underlying condition that might require medication, treatment, or even surgery.

If you experience long periods for more than three cycles, see your doc. Handling it yourself only delays treatment and could lead to more invasive treatments in the future.