Irregular periods​

You have irregular periods if the length of your menstrual cycle keeps changing and your periods may come early or late. After puberty, many women develop a regular cycle with a similar length of time between periods. Keeping track of your periods and symptoms on a menstrual cycle calendar or in an app is good way to learn what’s normal for your body, and help you know if anything changes. But it’s not uncommon for it to vary by a few days each time. There are many possible causes of irregular periods and sometimes they may just be normal for you.​

Common causes include:​

  • puberty – your periods might be irregular for the first year or two
  • the start of the menopause
  • early pregnancy 
  • some types of hormonal contraception
  • extreme weight loss or weight gain, excessive exercise or stress
  • medical conditions – such as polycystic ovary syndrome (PCOS) or a problem with your thyroid​

There might not be anything wrong, but it’s a good idea to get checked out to see what the cause might be. When to see a doctor​

  • your periods suddenly become irregular and you’re under 45
  • you have periods more often than every 21 days or less often than every 35 days
  • your periods last longer than 7 days
  • there’s a big difference (at least 20 days) between your shortest and longest menstrual cycle
  • you have irregular periods and you’re struggling to get pregnant.​


It is important as a Muslima to recognise the difference between your period and istihaadah (non-menstrual vaginal bleeding). A lot of the time, istihaadah bleeding happens when your period is irregular.​

The key thing to look out for when distinguishing the two are:​

  • Colour: menstrual blood is darker.
  • Consistency: menstrual blood is thick and heavy, whilst the blood of istihaadah is thin.
  • Smell: menstrual blood smells whereas the blood of istihaadah doesn’t.
  • Clotting: menstrual blood usually doesn’t clot but the blood of istihaadah does because it comes from a vein.​

If you have just finished your period and then started bleeding again, look to the above guide to know whether it is your periods again or istihaadah.​

There is a maximum length of time to be on your period for muslima’s – 15 days. Do your ghusl (purifying wash) on the 16th day as bleeding that is longer than 15 days is classed as istihaadah.​

For istihaadah bleeding, make sure to do your wudhu for each prayer.​

What happens if I had a regular cycle and then experience istihaadah?

So, you used to have regular periods – coming around the same time every month and lasting the same number of days. You are now having irregular bleeding and you don’t know what counts as your periods and what counts as istihaadah:​

  • You know your regular regular cycle i.e. how many days between your periods (usually 21-35 days apart) and how long it lasts:
    • Act as though you are on your period on your next calculated menstrual  cycle, even if the blood looks different. This means don’t pray e.t.c and then do ghusl and go back to praying when you believe your period has ended according to your previous cycles (even as you continue bleeding).​
  • If you know how many days your periods last but you can’t remember when in the month it used to come but you think you know i.e. you think it is as the end of the lunar month:
    • Go along with when you think it might be and then stick to however many  days you know your periods usually last (must not be over 15 days).​
  • If you don’t know how long your periods last because you don’t know when in the month it used to come:
    • Start counting your period from the beginning of each lunar month.​

What happens if my periods were always irregular?

So, if you always had irregular bleeding:​

  • If you never had a regular period before – you have been experiencing istihaadah since the first time you got your periods:
    • Distinguish between the different types of blood. You are on your period if it is dark / thick or has a distinctive smell to it. Anything other than that is istihaadah.
  • If you can’t tell the difference between your period and istihaadah i.e. because the blood is all the same:
    • You should follow the general period patterns of women, so your periods last six / seven days every month starting from the first time you saw blood. Anything after that is istihaadah.