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Heavy Periods: Symptoms, Causes and Getting Help

Your Health / Conditions / Iron Deficiency Anaemia / Heavy Periods: Symptoms, Causes and Getting Help​​​​​​​

Published on May 15, 2020
​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​Authored by Feisia Dam, BPharm(Hons)


Bleeding through a pad or tampon every 1-2 hours could mean heavy periods. In fact, what one woman considers "normal" could actually be "heavy" in medical terms.  Studies have shown that women have very different perceptions of what a heavy period is. We are here to set the record straight. In this article, we help you understand what is considered heavy menstrual bleeding, why it happens, what to look out for, and when it becomes vital to seek help from the doctor.

What is Heavy Menstrual Bleeding?

Menorrhagia is the medical term used to refer to heavy menstrual bleeding or prolonged menstrual bleeding. Traditionally, doctors will diagnose a woman with menorrhagia if she usually loses more than 80ml of blood each period or periods that last longer than 7 days. This excessive blood loss can have a considerable impact on the quality of your life.

How Do You Know If You Have Heavy Periods?

While there are the medical definitions, as mentioned above, experts have given more practical advice on what to watch out for:

  • Needing to change your pad or tampon every hour or two
  • Needing to use more than one sanitary product (e.g., layering pads) at the same time
  • Passing lumps of blood (also called clots) bigger than a 20 cent coin in Australia or a $2 coin in New Zealand
  • Needing to change your pad or tampon overnight; or needing to lay towels on the bed
  • Feeling weak, tired or fatigued

Women talk about the sense of anxiety when they're out, or in a meeting, and feeling like they're about to bleed through their sanitary products and must escape to the toilet immediately.

Why Is My Period So Heavy?

Heavy periods are often related to an underlying medical condition. That is why if you think you have heavy periods, you should talk to the doctor about it. Some reasons include uterine abnormalities, hormone imbalances, certain medications, malignancies, bleeding disorders and pre-menopause. In some cases, the cause is unknown.

Can Heavy Periods Make Me Tired?

Yes, heavy periods can make you tired. Here's why.​​​​​​​

Given that when you lose blood, your body also loses some iron. People with heavy periods over time can develop iron deficiency, and if untreated, iron deficiency anaemia. As a result, the body doesn't have the required iron reserves to create enough healthy red blood cells. Since red blood cells carry oxygen to fuel the cells throughout the body, iron deficiency anaemia can leave you feeling tired, pale, and short of breath.​​​​​​​

Seeing The Doctor About Heavy Periods

If you are worried about heavy menstrual bleeding, you should talk to your GP.  They will ask you questions to better understand your health, do a blood test and may also do a physical exam.

Get prepared for your appointment by recording some facts about your menstrual cycle and symptoms. Information such as:

  • The length of your cycle
  • Whether your periods are regular or not
  • How long your periods last
  • The level of disruption to your daily activities or quality of your life
  • The heaviness of your flow (spotting, light, medium, or heavy) on the different days of your period
  • Whether you get clots and how big they are

It is even more helpful if you can jot this down over a few cycles. You could consider using a period tracker app to help. By collecting this information, your doctor will have a better understanding of what’s going on.

Moreover, your doctor might ask you about:

  • Your pregnancy history (if any)
  • Any past and present medical conditions
  • Past medical surgeries you may have undergone
  • Your past and current medications
  • The type of birth control method you use
  • Your family's medical history

Questions To Ask Your Doctor

Now that your doctor has more precise information about your symptoms, it's time for you to raise some questions of your own.

These questions can help guide the conversation with your doctor about how best to manage your heavy periods.

  • Do I need to undergo any tests?
  • Do I need to see a gynaecologist?
  • What are the management options, and what are the advantages and disadvantages of them?
  • What if I'm trying to conceive now or in the future?
  • When should I see an improvement?
  • How frequently should I see you for check-ups?

Click here to download the questions and note down any additional ones that you might have. Take it along to your appointment so you can get the most out of the time with your doctor.

Last updated: 15/08/2019


    1. NICE guidline: Heavy menstrual bleeding: assessment and management. Published 14 Mar 2018
    2. Douglas LA, Davis AM. Assessment and Management of Heavy Menstrual Bleeding. JAMA Clinical Guidelines Synopsis. 2020;323(3):270-271
    3. Bradley LD, Gueye NA. The medical management of abnormal uterine bleeding in reproductive-aged women. Am. J. Obstet. Gynecol. 2016;31-44
    4. Hallberg L, Hogdahl AM, Nillson L, et al. Menstrual Blood loss – a population study. Acta Obstet Gynecol Scand 1966;45:320-351
    5. Hapangama DK, Bulmer JN. Pathophysiology of heavy menstrual bleeding. Women’s Health 2016;12(1):3-13
    6. Warner PE, Critchley HO, Lumsden MA, et al. Menorrhagia I: measured blood loss, clinical features, and outcome in women with heavy periods: a survey with follow-up data. Am. J. Obstet. Gynecol. 2004; 190(5), 1216–1223
    7. Warner PE, Critchley HO, Lumsden MA, et al. Menorrhagia II: is the 80-mL blood loss criterion useful in management of complaint of menorrhagia? Am. J. Obstet. Gynecol. 2004;190(5), 1224–1229
    8. Shoep ME, Nieboer TE, van der Zanden M, et al. The impact of menstrual symptoms on everyday life: a survey among 42,879 women. Am. J. Obstet. Gynecol. 2019;220:569e1-e7
    9. Camaschella C. Iron-deficieny anemia. N Engl J Med. 2015;372:1832-43.

    Last reviewed: 15/08/2019


    External Resources

    -Royal Women’s Hospital: Heavy Periods
    -Jean Hailes
    -Family Planning New Zealand: Abnormal Periods
    -Health Navigator New Zealand

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