SummaryRead the full fact sheet
- Amenorrhoea is the absence of menstrual periods.
- The most common cause is hormone disruption, which can be due to emotional stress, extreme weight loss, excessive exercise or certain reproductive disorders.
On this page
- About absent periods
- The menstrual cycle
- Is it normal to miss one or more periods?
- Primary amenorrhoea
- Secondary amenorrhoea
- Athletic amenorrhoea
- Getting a diagnosis for amenorrhoea
- Health risks of amenorrhoea
- Treatment options for amenorrhoea
- When to see your doctor
- More information
- Where to get help
About absent periods
Periods are a natural part of the menstrual cycle. Periods usually happen every month.
Amenorrhoea is when you don’t get your period at all.
The menstrual cycle
The menstrual cycle prepares your body for pregnancy. If you are not pregnant, your hormones send a signal to your uterus to shed its lining. This is your period. Once your period starts, the cycle begins again.
A menstrual cycle is measured from the first day of your period to the first day of your next period. The average length of a menstrual cycle is 28 to 29 days, but every woman’s cycle is different.
Menstrual cycles can be longer at different times in your life. For example, when you get your first period, in the first 2 years after your periods start and in your teenage years (between the ages of 10 and 15 years).
Is it normal to miss one or more periods?
It’s normal to miss periods at different times in your life.
- when you first start getting your periods
- while pregnant
- while breastfeeding
- in the lead-up to menopause (your final menstrual period).
Primary amenorrhoea is when menstrual periods haven’t started by the age of 16 years. This doesn’t happen often.
- abnormality or absence of reproductive organs
- lack of hormones needed to start getting periods
- genetic or chromosome abnormalities, such as Turner's syndrome.
Secondary amenorrhoea is when periods stop for 3 months or more in a row. This is normal in pregnancy and in the lead-up to menopause.
Other causes include:
- excessive exercise or intense athletic training
- low body weight and poor nutrition – for example eating disorders such as anorexia nervosa
- severe anxiety and depression
- medications such as antipsychotics
- some oral contraceptives or intrauterine devices (IUDs)
- polycystic ovarian syndrome (PCOS)
- premature menopause
- problems with glands, including the thyroid and the pituitary gland.
Athletic amenorrhoea is when elite or excessive exercise suppresses the release of oestrogen, causing periods to stop.
Getting a diagnosis for amenorrhoea
Your doctor may ask about your medical history and do different tests to find the cause of the amenorrhoea.
- a pregnancy test
- a physical examination
- blood tests to check your hormone levels
- scans of your abdomen, pelvis, reproductive organs and skull (to check the pituitary gland).
Health risks of amenorrhoea
Low levels of oestrogen in the body can:
- reduce fertility
- reduce your chances of falling pregnant
- increase the risk of cardiovascular disease – such as high blood pressure
- increase the risk of early onset osteoporosis – a long-term disease that makes your bones less dense and more fragile
- cause premature menopause and ageing.
Treatment options for amenorrhoea
Treatment of amenorrhoea depends on the cause. If the amenorrhoea is caused by another condition, that condition will be treated first. This may help your periods start again.
Treatment may also involve:
- hormone therapy
- nutritional advice
- counselling (in the case of an eating disorder).
When to see your doctor
See your doctor if:
- you have missed 3 or more periods in a row
- you have had fewer than 9 periods in a year
- you have noticed changes in the pattern of your periods.
You can also ask your doctor for advice if:
- a 13-year-old girl is not showing any signs of puberty (for example breast development)
- a 16-year-old girl has not started her period.
For more detailed information, related resources, articles and podcasts, visit Jean Hailes for Women’s Health.
Where to get help
- Shufelt CL, Torbati T, Dutra E 2017, ‘Hypothalamic amenorrhea and the long-term health consequences’, Semin Reprod Med, vol. 35, no. 3, pp. 256-262.
- Klein D, Paradise, SL, Reeder, R 2019, ‘Amenorrhea: A systematic approach to diagnosis and management’, Am Fam Physician, vol. 100, no.1, pp. 39-48.