SummaryRead 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.
What is a heavy period?
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.
Difference between heavy periods and irregular menstrual bleeding
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 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 , including or
- – when cells similar to those that line the uterus grow in other parts of the body
- endometrial – growths in the inner lining of the uterus
- – when the endometrium grows inside the muscle of the uterus
- – non-cancerous growths within the uterus wall
Diagnosing heavy periods
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
- an test
- to check for various conditions including
- an .
Your doctor may refer you to a specialist if:
- there is evidence of , adenomyosis or 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 or transexamic acid
- recommend certain – such as an , or ).
- suggest surgery – such as a hysteroscopy, endometrial ablation or for more serious conditions.
More information on heavy periods
Where to get help
- 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] . 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.