Summary
Read the full fact sheet- Heavy or abnormal periods may be an indication of other health problems.
- About 25% of women lose lots of blood when they have their period.
- Learn more about the effects of heavy periods, the causes, treatment options and where to get help.
On this page
What is a heavy period?
About 25% of women lose lots of blood when they have their period. The amount of menstrual blood loss can change at different times in your life.
A heavy period (also called 'menorrhagia' or 'abnormal uterine bleeding') is heavy bleeding of more than 80ml (1/3 cup) each menstrual cycle.
Symptoms of heavy periods include:
- excessive bleeding that lasts longer than 7-8 days
- bleeding or ‘flooding’ of your pad or tampon (especially the largest sizes)
- needing to change your pad or tampon every two hours or less
- needing to change your pad or tampon overnight
- blood clots that are larger than a 50-cent piece.
Your period shouldn’t interrupt your daily activities, or cause stress or anxiety.
Difference between heavy periods and irregular menstrual bleeding
Irregular vaginal bleeding is any bleeding from a woman’s vaginal area and usually refers to bleeding that is not part of a regular period. The range of causes includes infection and hormonal changes.
If you suffer from ongoing bleeding problems, see your local doctor for a full assessment to make sure there is no underlying disorder causing the problem.
Health effects of heavy periods
Heavy blood loss from your period can affect you in many ways.
For example, you might:
- feel tired, exhausted or dizzy
- look pale
- have low iron levels
- have cramping and pain in your lower abdomen
- worry that bleeding will soak through your clothes.
Causes of heavy periods
In many cases, it’s hard to know the exact cause of heavy periods.
The cause of heavy periods in about 50% of people is the uterus lining grows more than usual. This lining sheds to create a period.
Other common causes of heavy menstrual bleeding include:
- complications of pregnancy, including ectopic pregnancy or miscarriage
- polycystic ovary syndrome (PCOS)
- endometriosis – when cells similar to those that line the uterus grow in other parts of the body
- endometrial polyps – growths in the inner lining of the uterus
- endometrial cancer
- adenomyosis – when the endometrium grows inside the muscle of the uterus
- fibroids – non-cancerous growths within the uterus wall
- intrauterine device (IUD).
Diagnosing heavy periods
See your doctor if you are worried about heavy periods.
They might ask about your general health, medical history, sexual activity and plans to get pregnant.
Tests for heavy periods
Your doctor may do some tests to learn more about your heavy periods.
For example, they might do:
- a physical examination of your vagina and uterus
- a pregnancy test
- an iron test
- a cervical screening test
- blood tests to check for various conditions including anaemia
- an ultrasound.
Your doctor may refer you to a specialist if:
- there is evidence of fibroids, adenomyosis or polyps on your ultrasound
- your bleeding doesn’t improve after 6 months of treatment.
Treatment for heavy periods
Treatment options depend on the cause of your heavy periods, life stage and medical history. To reduce pain, inflammation and blood loss, your doctor might:
- prescribe medicines – such as non-steroidal anti-inflammatory drugs (NSAIDs) or transexamic acid
- recommend certain forms of contraception – such as an intrauterine device (IUD), the pill or progestin-only pill).
- suggest surgery – such as a hysteroscopy, endometrial ablation or hysterectomy for more serious conditions.
More information on heavy periods
For more detailed information, related resources, articles and podcasts, visit Jean Hailes for Women's Health.
Where to get help
- GP (doctor)
- Gynaecologist
- Family planning clinic
- Sexual Health Victoria. Tel: (03) 9257 0100
- Jean Hailes for Women's Health
- Hallberg L, Högdahl AM, Nilsson L, Rybo G. Menstrual blood loss – a population study. Variation at different ages and attempts to define normality. Acta Obste Gynaecol Scand. 1966;45(3):320–51.
- Heavy menstrual bleeding; assessment & management. NICE guideline [NG88] www.nice.org.uk/guidance/ng88. March 2018
- Quinn S, Higham J. Outcome measures for heavy menstrual bleeding, Womens Health 2016;(1) 21-26.
- Davies J, Kadir RA. Heavy menstrual bleeding: an update on management. Thromb. Res 2017, 151(1):70-77.
- Kocaoz S, Cirpan R, Degirmencioglu AZ. The prevalence and impacts heavy menstrual bleeding on anemia, fatigue and quality of life in women of reproductive age. Pak J Med Sci. 2019;35(2):365-370. doi:10.12669/pjms.35.2.644.