An Overview of Heavy Menstrual Bleeding

The Causes, Symptoms, and Diagnosis

Experiencing heavy or prolonged menstrual bleeding—the medical term is menorrhagia—can be alarming and nerve-wracking. While this is a common experience, heavy menstrual bleeding does warrant a visit to your doctor, preferably your gynecologist.

causes of heavy menstrual bleeding
Verywell / Brianna Gilmartin


The easiest way to know if you are experiencing heavy menstrual bleeding is to take note of how often you are soaking through a pad or tampon.

If your period is heavy enough to require changing a pad or tampon every hour for several hours, or if you have vaginal bleeding that lasts more than a full week, you are experiencing heavy menstrual bleeding.

Besides these two, other signs of heavy menstrual bleeding include:

  • Wearing more than one pad at a time in order to control the bleeding
  • Having to change your tampon or pad in the middle of the night
  • If your menstrual blood contains clots that are the size of a quarter or bigger

When Menstrual Bleeding Is an Emergency

Go to the nearest emergency room if you experience severe, acute bleeding in which you soak through four or more pads or tampons in a two-hour period. If you are pregnant, seek immediate medical care with any bleeding.


There are a number of different causes of heavy menstrual bleeding—some benign (non-cancerous) like fibroids, and some more serious like cancer of the uterus or cervix. Other causes are not structural but have to do with hormone changes or bleeding problems within your body.

Ovulatory Dysfunction

Ovulatory dysfunction during adolescence or perimenopause is the most common cause of heavy menstrual bleeding. During this time, ovulation (releasing an egg) can be irregular, which means not every month or not at all. This leads to thickening of the uterine lining and heavy periods.

Beyond the normal hormonal changes that occur with puberty or menopause, ovulatory dysfunction can also occur with hypothyroidism, polycystic ovary syndrome (PCOS), and premature ovarian insufficiency.

Treating the underlying problem is critical to restoring normal ovulation and normalizing periods. If irregular ovulation is part of the body's normal response (for example, puberty or perimenopause), birth control methods or hormone therapy, respectively, can usually ease up the bleeding.

Uterine Fibroids

Fibroids are usually benign (non-cancerous) growths that develop from the muscle of the uterus. They are most often seen at ages from 30 to 49 years.

While the cause of uterine fibroids is unclear, it is known that they are estrogen-dependent. This is why certain hormonal birth control methods like birth control pills can help reduce heavy menstrual bleeding from fibroids.

Often, when symptoms are not severe or troublesome, it's sufficient to take a “wait and see” approach with uterine fibroids. And once menopause occurs, fibroids typically shrink and disappear without treatment.

Progestin-release intrauterine devices (IUDs) can decrease menstrual bleeding but do not reduce fibroid size. Injectable gonadotropin-releasing hormone agonists can decrease the size but can only be used for a short time due to side effects.

Endometrial ablation (the lining of the uterus is destroyed) is a procedural treatment for small fibroids. Surgical options include myomectomy (removal of the fibroid) and uterine artery embolization (the blood supply is cut off to the fibroid).

In the most severe cases, a hysterectomy may be warranted, in which the whole uterus is removed, with or without the ovaries.

Uterine Polyps

Polyps in the uterus—called endometrial polyps—are typically non-cancerous, grape-like growths that protrude from the lining of the uterus. They can occur both before and after menopause. The cause of endometrial polyps is unclear, though research suggests a link between postmenopausal hormone therapy and obesity.

Treatment of small polyps is unnecessary unless you're at risk of uterine cancer. If you are, a polypectomy would be performed to remove the polyp for evaluation in the lab. Larger polyps are routinely removed and examined as a precaution.

Uterine Adenomyosis

In this condition, the uterus becomes enlarged because cells of the uterus grow into the muscular wall of the uterus, causing painful and heavy bleeding. While bleeding can be reduced with hormonal birth control methods, the definitive treatment for adenomyosis is a hysterectomy.

Pelvic Inflammatory Disease (PID)

PID is most often caused by an untreated sexually transmitted infection, however, it can sometimes occur following childbirth, abortion, or other gynecological procedures. In PID, one or more reproductive organs are infected, like the uterus, fallopian tubes, or cervix. The recommended treatment for PID is antibiotic therapy.

Cervical or Endometrial Cancer

Cervical cancer occurs when cells in the cervix become abnormal, multiply out of control, and damage healthy parts of the body. The human papillomavirus (HPV) is the cause of the vast majority of cervical cancers. Treatment for cervical cancer includes surgery, chemotherapy, and/or radiation therapy.

Endometrial cancer occurs when abnormal cells in the endometrium (the lining of the uterus) multiply out of control and damage the uterus and other organs. While the cause of endometrial cancer is unknown, people diagnosed with this type of cancer tend to be in their mid-60s.

The first treatment for endometrial cancer is usually a hysterectomy, possibly followed by chemotherapy and/or radiation treatments.

Early diagnosis is key to the effective treatment of cancer. In addition to regular Pap screening for cervical cancer, the American Cancer Society recommends that women at high risk of endometrial cancer be given an annual endometrial biopsy.

Bleeding Disorders

While there are several types of bleeding disorders, the most common type in women is von Willebrand disease (VWD). Treatments for von Willebrand disease involve the release of stored clotting factors in the blood or, in extreme cases, replacing the clotting factor with an intravenous treatment or with a prescribed nasal spray.

Other bleeding problems like having a low platelet count (platelets are involved in the clotting process and are produced in the bone marrow) or being on a blood thinner like Coumadin (warfarin sodium) can also be the culprit behind heavy menstrual bleeding.

Other potential causes of heavy menstrual bleeding in non-pregnant women include endometriosis and having an intrauterine device (IUD) like the Mirena, especially during your first year of use, but the list does not stop there. This emphasizes the importance of seeing your doctor for a proper diagnosis and evaluation.


Diagnosing the cause of heavy menstrual bleeding can be a bit of a protracted process, so it's best to be prepared. Before your appointment, try to jot down your period pattern in the last few months.

For instance, how many days did you bleed each month? How many pads or tampons do you go through on the days of your heaviest menstrual flow?

In addition, it's a good idea to make a list of all your medications, including hormonal birth control, hormone therapy, and any vitamins or over-the-counter supplements. In figuring out why you are bleeding heavily, do not be surprised if your doctor orders a series of tests, in addition to performing a pelvic exam.

These tests may include:

  • A pregnancy test (if premenopausal)
  • Blood tests (for example, a complete blood count, iron levels, and thyroid hormones)
  • An ultrasound of your pelvis

Your doctor may also perform a procedure in the office called a hysteroscopy in order to visualize the inside of your uterus. They may also take a sample of your uterine tissue, called an endometrial biopsy, depending on your age and your individual symptoms.

A Word From Verywell

Getting to the bottom of your heavy menstrual bleeding is important not only for your quality of life but for your health as well. Heavy blood loss, regardless of the cause, can cause iron deficiency anemia, which can make you short of breath, tired, and dizzy.

Once both the bleeding and the root cause of your bleeding are addressed and treated, you can move forward and feel well—you deserve it.

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Article Sources
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