Experiences with
Irregular periodsCheck if you have irregular periods
The average gap between periods starting (the menstrual cycle) is around 28 days. It can sometimes be a bit shorter or longer.
A woman's periods are irregular if the gap between them is less than 21 days or more than 35 days.
Irregular periods can affect anyone who has periods.
It's more likely for your periods to be irregular when they first start during puberty, and when you're nearing menopause.
Keeping track of your periods
Using an app or a diary to keep track of your periods can help you see if they're irregular.
Day 1 of your menstrual cycle is the first day of your period. The last day of your cycle is the day before your next period.
Causes of irregular periods
Common causes of irregular periods include:
- puberty, when you start your periods
- the start of menopause (usually between the ages of 45 and 55)
- pregnancy – a missed period is often an early sign of pregnancy
- hormonal contraception like the progestogen-only pill, contraceptive injection and intrauterine system (IUS)
- losing or gaining a lot of weight
- stress and anxiety
- exercising too much
Sometimes, conditions like polycystic ovary syndrome (PCOS) and an underactive thyroid gland can cause irregular periods.
- your periods are irregular
- your periods last longer than 7 days
- you have irregular periods and other symptoms like weight gain, tiredness, hair growth on your face and dry or oily skin
- your periods are irregular and you're struggling to get pregnant
Treatments for irregular periods
Treatment is not always needed for irregular periods.
The GP may refer you to a specialist (gynaecologist) if you need tests to find out what's causing your irregular periods. If treatment is needed it will depend on the cause.
For example, if a condition like polycystic ovary syndrome is causing irregular periods, the combined pill may help make your periods more regular.
SymptomsCausesMedical treatmentsYour periods are irregular if you have them more often than every 21 days or less often than every 35 days.
Causes of irregular periods include puberty, the start of menopause, pregnancy and some types of hormonal contraception.
Treatment is not always needed for irregular periods. If treatment is needed, it will depend on the cause.
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HealthUnlocked contains information from NHS Digital, licensed under the current version of the Open Government Licence
