A lot of you tell me that you use apps to track your menstrual cycles (periods, ovulation, and when you are most fertile). Great, but did you know they’re actually not that accurate? Especially the apps which just rely on you putting the dates when you get your period. This article explains why that is, and also shows you how to track your own menstrual cycle.
Menstrual tracker apps are often not that accurate
Periods don’t always arrive at the same time for everyone. So one person your age could have a cycle that lasts 25 days, and someone else could have one which is 35 days. Also, cycles can be random from person to person. So you might have a 28 day cycle, followed by a 32, followed by a 25.
Even if you have a regular period arriving every 28 days (which is not common) your ovulation date can vary. It’s not always at the same time, either from person to person or from cycle to cycle. The tracker apps use algorithms provided by all the data that the millions of users provide them with. Even though they are using this big data, they are often not accurate, because real, actually occurring, periods and ovulation are random.
So unless your app is asking you to input your daily temperature (using a thermometer in your mouth), or to check your vaginal discharge, or are giving you a urine test to do at home, it’s not likely to be very accurate.
There’s much more about how fertility works here, if you are confused about this.
Why track your cycle at all?
You don’t have to track your menstrual cycle at all, many people don’t. Some people like to do it because they want to know when they can expect their period. Others do it because it’s fun. Also people like to do it if they are planning for a pregnancy. And some people do it if they are planning to definitely not get pregnant.
Remember, if you are definitely not wanting to get pregnant, there are other much more effective methods of contraception (aka birth control). The reason that tracking your cycle (known as ‘natural family planning’ or the ‘rhythm method’) isn’t that effective is that it’s very hard to work out when you are fertile and not fertile. Remember also that it’s possible for sperm to survive for up to 5 days inside someone. So the non fertile time of the cycle (when you can have sex and not get pregnant) is longer than you might think (and longer than many apps predict).
There’s much more about finding the right contraception for you here.
It’s a way to be with your body, not against it
A really important thing to bear in mind is that you can track what your body has done, and what it might do, but bodies are always changing. So if you are interested in tracking your cycle do so kindly and patiently and be prepared to be surprised. It’s about working with your body, not expecting it or making it do things it doesn’t want to do.
Find out more about what might happen in your body when you go through puberty.
Track your menstrual cycle without an app
Rather than relying on an app to tell you when your period is going to arrive, you could instead track your own using the old fashioned method. It won’t be any more accurate than using an app, but there are several advantages to tracking your own:
- You’re not giving your data to a big company
- It might help you feel more connected with your body (rather than an app telling you what your body is doing, you might instead understand your own body a bit more)
- It can be fun and creative
Here is a yearly calendar you can use. You can print it out (or get your school to print it out for you) or just use on a phone (a printed version might be more fun).

Of course you can just use a regular diary or calendar too. Hey maybe I will make a BISH calendar for 2024? Let me know if you’d like that. If you have been using an app, you could copy the information you have put into your app into a regular calendar like this.
Tracking your period
The first day of your cycle is when your menstrual cycle starts. You could mark it with a red dot and/or a number 1. You could track how strong the flow of your period by putting a dot which gets bigger or smaller.
You could also track how comfortable / uncomfortable the cramping is. Remember that the muscles around your uterus are helping to push the sticky mucus and blood which forms the womb lining. The muscles are working really hard and that can cause cramps. So perhaps you could note how hard they are? Use a star perhaps? Or another symbol.
Sometimes there might be a little bit of blood in between periods which is known as ‘spotting’. Usually this is absolutely nothing to worry about, there’s more about this at the NHS website. That’s also something else you could track.
Tracking your mood / general vibe
Then during your menstrual cycle you could track some other things too. You could track your general mood. Obviously how you feel is complex and to do with the outside world as well as what’s happening in your body. But if you feel like your body is more responsible for a particular mood, you could monitor it. Speaking to a womb haver just now, she said she feels: frustration, foggy head, sensitive, horny, relieved, tired, angry, sad, hungry, among other things. How about you? You can probably find emojis for these things, or draw your own 🙂.
You could also note what kinds of emotions you might be feeling due to outside pressures. Or anything else going on in your life. Our bodies can change our emotional state, but our emotional state can also change our bodies (this is true whether you have a uterus or not). For example, stress can change menstrual cycle length.
Tracking ovulation signs
It’s harder to track ovulation (when you release an egg) than periods. Periods are much more obvious because you can see them. But you could pay attention to your discharge at the opening of the vagina. It changes throughout your menstrual cycle. Sometimes there’s not much, then it might get a bit thicker and creamier, then it gets sticky and slippery, then it gets clearer and wetter. Around the time of ovulation it starts to get slippery and stretchy, like raw egg whites (if you know what that looks like). This is when you are most fertile. When it changes to being clear and watery is when you are less or not fertile.
Around ovulation some people get a pain on one side of the lower abdomen, which is when the egg is just about ready to be released from the ovary. It’s called ovulation pain or mittelschmerz (German for middle pain). About 40% of people who get periods get this additional pain, which can be mild or really painful. It usually lasts between 3 and 12 hours. So you could track that too if you get it.
If you have a medical thermometer you could do daily readings of your body temperature so that you can check your baseline. If your temperature goes up a bit it can be a sign that you are ovulating. However, the change in temperature is not very high (less than 0.5 of a degree) so it can be tricky to do this.
Other things you can track
You could also track any other changes that your body experiences during your cycle if you like. For example, if you feel bloated in your tummy, or your skin changes, or your chest feels sore. Some people find it hard to poo at various times, or poo more, or might have smellier farts! Just try to be curious about what happens for you 💩.
Then what?
After you have tracked your menstrual cycle a few times, you might start to see some patterns that emerge for you. Everyone is different and everyone’s cycles are different and sometimes random. But after a while you might start to have a better understanding of your body and how you relate to it.
Here’s a made up example of what a year of menstrual cycles might look like. Make up your own system of dots and squiggles and symbols.

See how it goes! At least it gets you off your phone for a bit every day too 🙂
Further reading
Chella Quint has written a couple of lovely books about periods and menstrual cycles. One’s called Own Your Own Period, which is for younger readers. The other is called Be Period Positive. You can find out more about them at Chella’s website called Period Positive. There are also lots of resources there for schools to do better at helping people with their periods.
Here’s another explainer from Planned Parenthood about how you can track your cycle without an app.
Hope you find that helpful!
Justin
© Justin Hancock, 2024 Find out more about me and BISH here.

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Hi, Bish! Just want to ask if I ovulated because of some signs? So my last period started august 22 and i have pretty normal cycle. And on september 3, i felt a little cramps in my lower abdomen and I have high sexual drive for the last weeks. Is this a possible sign that I have ovulated on september 3?
Hi Geni. It’s really difficult to work out when you’ve ovulated (and even harder for me given that it’s not my body we are talking about). The pain you describe could be a sign of the ‘middle pain’ that people get around ovulation, but it could also have been something else. There are lots of tips in the article above about how to track your cycle but it will take you a few cycles to notice the signs. If you are wanting to prevent pregnancy the best thing to do is to use a method of contraception (which can also include not having penis in vagina sex)