Tally chart to track periods

2 day periods? 1 day periods? Or maybe even 2 periods in a month? Our menstrual cycles can surprise us and throw the unexpected our way. But just how long is a period supposed to last?

Desperately checking your underwear to see when your period finally starts? Or maybe you’re anxiously waiting for it to be done? Sometimes our flow doesn’t come at all while at other times, it seems to never end. But your period should never hold you back or stop you from doing what you want! And getting an idea of how long it could last for can make it easier for you to plan some activities, holidays or even outfits.

And while there’s no straightforward answer to how long periods should last, getting clued up on what’s normal and what could cause longer or shorter periods can help you better understand your body.

What is the average length for a period?

When it comes to our bodies, an average time for anything can be pretty hard to predict – each is unique and we can never really know for sure how they’ll react. But generally speaking, periods work on a cycle from around 21 up to 40 days. [1] Menstruation (your period) happens within this cycle for around 3–8 days and the day your flow starts is considered as the first day of your menstrual cycle. Since there’s a wide range of what’s considered to be a “regular” period length, it’s not very useful to compare ours with those of other people – every body and menstrual cycle is different!

On the other hand, sometimes periods can be completely irregular and may not follow a pattern consistently. You could experience spotting, particularly heavy periods, 1 day periods or maybe even 2 periods within a couple weeks (if you have a very short cycle). This may seem unsettling and worrying at the time, but often it’s just a sign of your body adjusting to some kind of hormonal change. Your period should eventually regulate itself naturally.

Of course, if you do persistently experience extremely heavy or irregular periods for several months, or simply feel that something is wrong, you can always book an appointment with your doctor so that they can best advise you and come up with a solution if needed.

How long does your first period last?

If you’re just starting puberty, you may be eagerly waiting for your first period, but chances are you have not given as much thought to what happens once you’ve got it and how long it will stick around for. Basically, there’s no universal number for how long your first period could be – we’re all different! However, it’s worth knowing that it will most likely be very light and only last a couple of days.

This is because your body is learning how to adapt to new levels of the hormones oestrogen and progesterone (which are produced during puberty). [2] But after a few months your period should regulate itself and get a pattern that’s normal for you.

How many days are there between periods?

Figuring out when to expect your next menstrual flow can be really helpful so you can prepare; whether by having spare period products in your bag or even planning some PMS selfcare rituals!

There aren’t an exact number of days that everyone will experience in between periods. All our bodies will deal with hormones and menstrual cycles differently, meaning either longer or shorter waits in between periods. It’s also normal to experience changes in your cycle from month to month, so just because there were 24 days between your periods last month, it doesn’t mean that it will be exactly the same next time.

Factors that can affect the length of your period

Hormone levels

Period length can change constantly over time, and sometimes there may not be a specific explanation for why it is suddenly longer or shorter. Our bodies don’t run like clockwork so we shouldn’t expect them to! 

However, hormone levels are generally the main reason as to why the length of periods may change. So let’s take a look at which specific factors can affect our hormones.


Drastic changes in hormone levels occur during puberty (an increase in oestrogen) around the ages of 8–14 and then again during perimenopause and menopause (a decrease in oestrogen and progesterone) around the ages of 45–55. [3][4] So irregular or frequent periods as well as spotting are common during these times in our life as our bodies adjust. If you’re going through either change, try to be patient -it is normal for your body to take its time!


Some contraception can also affect the length of our periods. For example, methods such as the hormonal coil or the implant have the hormone progesterone in them. This added progesterone in your body thins the lining of the womb and can cause your menstrual flow to be lighter and shorter. [5]

If you’ve like to find out more about this, head over to our article on how contraception can affect your period.

General health

Health conditions such as endometriosis (which tends to make periods last longer due to more uterus lining to shed) and PCOS (which can cause irregular cycles or stop periods altogether as eggs aren’t released regularly) can all change the duration and frequency of your periods. [6][7]

Similarly, stress can also affect how long your menstrual flow lasts. It is ironically easy to stress about being stressed, but taking the time to do something you like and relax is really important to prevent it from affecting your cycle. So try your best to listen to your body and let it loosen up. If you need help, you can always reach out to a friend or get in touch with a therapist. And if you find that your irregular periods continue to happen, it’s a good idea to check in with your doctor for some medical advice.

How can I deal with the length of my periods?

There’s no failsafe way you can manage the length of your periods, but there are definitely things you can do to make it easier to deal with, such as taking the birth control recommended by your doctor. There are also ways you can temporarily stop or delay your period if you really need to for a special occasion or event.

In general though, it’s worth being prepared by noting down PMS symptoms and period days in a diary or on a period tracker, so that you can better understand what “normal” means for your body. It’s also helpful to keep some period products at hand just in case your menstrual flow comes unannounced!

Even though the length of periods can really change from month to month, hopefully understanding a bit more why these changes can happen will help to put your mind at ease – especially if you started noticing some differences lately. And while it may be inconvenient and a little stressful not knowing exactly when your period could start or finish, that’s just how nature works. Give yourself time to learn to recognise the rhythm of your body!

With so much to learn about our menstrual cycles, why not check out our other articles on period poop and why you may gain weight during your period?

Medical disclaimer

The medical information in this article is provided as an information resource only and is not to be used or relied on for any diagnostic or treatment purposes. Please consult your doctor for guidance about a specific medical condition.


[1]  https://www.nhs.uk/conditions/periods/

[2]  https://www.nhs.uk/conditions/periods/starting-periods/

[3]  https://www.nhs.uk/live-well/sexual-health/stages-of-puberty-what-happens-to-boys-and-girls/

[4]  https://www.nhs.uk/conditions/early-menopause/

[5]  https://www.medicalnewstoday.com/articles/326543

[6]  https://www.nhs.uk/conditions/endometriosis/

[7]  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5542050/

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