The most important female hormones you’ve gotta know

Hormones play a very important role not only in your menstrual cycle but in overall health. Sometimes they sound a little difficult to wrap your head around but we’re here to help break it all down. Here is what you really need to know about your female hormones.

You can think about hormones as your body’s communication system. They trigger a lot of important processes such as making you feel hungry or tired. During your menstrual cycle, these hormones rise and fall in a specific pattern causing changes in your body. Some you can see, such as your period, but others you cannot, such as ovulation.

Estrogen: the hormone behind your period

This hormone fluctuates over the course of your cycle. A gradual rise in the level of estrogen in the first two weeks of the menstrual cycle — the follicular phase  — is what causes your uterine lining to build up each month.

You might notice that your sex drive tends to increase in the days leading up to ovulation. Once you have ovulated your estrogen levels drop quite sharply, which might cause you to feel down, but they start to rise again a little until your period comes along.

If no pregnancy occurs, which is most often the case, estrogen (and progesterone) levels will drop again in the second phase of the cycle, causing your uterine lining to be shed i.e. your period and your next cycle to begin.

Luteinizing hormone: makes you ovulate

This is the hormone that causes your egg to be released from the ovary. As with all hormones, LH is present throughout the cycle, yet the surge happens just before ovulation.

This is why Natural Cycles will ask you to test for LH for a couple of days before you are expected to ovulate. It indicates whether your body is getting ready to ovulate or not. A positive result is a great indicator that you are likely about to ovulate, but the app can only confirm if you have ovulated with following high temperatures which are caused by….

Progesterone: causes your temperature rise

Progesterone levels shoot up once an egg was released from your ovaries i.e. ovulation has occurred.

This hormone causes your body to warm up a little. If you take a look at your Natural Cycles graph – you will see that your temperature is higher after you have ovulated. This is the main indicator the algorithm uses to identify your ovulation.

Should a woman become pregnant, the progesterone levels will continue to rise and so will her temperature. Whereas you will see your temperature drop again as progesterone drops once your period arrives.

Progesterone, though essential for reproduction, can bring along annoying symptoms for women during the last two weeks before your period.

These symptoms more commonly known as PMS include bloating, breast tenderness, and acne. It helps to keep track of these symptoms in the app and even things like exercising can help to counteract.


Your female hormones determine what goes on during your menstrual cycle and the changes you experience during the different phases. So getting to know them will explain a few things not only about how your body works but also how tracking your temperature can identify your ovulation and fertile days.

Your Natural Cycles team


Natural Cycles just closed another investment round

We are ecstatic to announce that we have just closed another investment round. This will allow us to reach even more women with Natural Cycles and keep advancing research in women’s reproductive health.

Our third and largest financing round in Natural Cycles history brought in an investment of 30 million dollars and we are absolutely humbled by it. The boost will contribute to bringing Natural Cycles to the next level in the best possible way, so here’s a quick breakdown of how we intend to leverage it:

Bulking up the medical team

For us to scale globally, we will need more people hands-on in all areas of the company. Currently, we are a team of 43 employees and our plan is to grow our international team even more next year. By adding doctors and more physicists from CERN we will bring Natural Cycles to the next level.

Product development

Our product team is working day in and day out on improving things in the app, making it easier and more fun to use. With our new team members, we will continue developing more features and making constant improvements so we can create the best possible Cycler experience.

Educating even more women

It’s our mission to continue to educate women about their bodies and menstrual cycles. It’s time to break the taboo around the topic and start openly talking about it. With Natural Cycles we not only want to give more women an effective method of contraception to choose from but a powerful tool so they can make informed decisions.

Because we truly believe that #yourcyclematters, and so does everyone else’s.

This past year has been huge here at Natural Cycles and full of successes. We have been certified as a contraceptive in Europe, hit pharmacy shelves, published our third and largest prospective clinical study and now this. Without our Cyclers and our great team we wouldn’t be here today – so once again it’s time to drop another thanks and praise to all.

Your Natural Cycles team

Natural Cycles is hitting pharmacy shelves

This week we have reached another milestone here at Natural Cycles – we will be hitting pharmacy shelves for the very first time this month. From now on our lovely purple thermometer, along with a 6-month subscription code will be available for instant purchase at Apoteket, Sweden’s oldest and most renowned pharmacy.

We are very happy to see Natural Cycles in stores, also because Apoteket handpicks their products very carefully, ensuring to only stock their shelves with the highest possible quality. The pharmacy only presents ethical and sustainable companies that are in line with their core values.

This big step allows us to bring Natural Cycles to even more women and we would love to see Natural Cycles represented in pharmacies all over the world one day.

Our offline Natural Cycles version has got everything you need to get started and will also be snuggly packed into our brand new and colourful packaging, created by our very own Design team. We had a quick chat with them to find out what their thoughts were behind the packaging and how they came up with it:

“We wanted to create something unique because that’s what we’re all about. Every woman and every cycle is different and this packaging reflects that. It looks different from every angle and that’s what I like about it.” – Daniel, Head of Design


Let’s keep pushing for Natural Cycles to become available for all women worldwide.


Your Natural Cycles team

Cycler Story: “To learn about your own body in real time is a massive eye-opener.”

Thousands of women are using Natural Cycles every day and we love getting to know them and hearing their inspiring stories. This time around we have a chat with Beccy from Bristol, she talks about how much she loves nerding out on her data and how learning about her body has been an eye-opener.

Tell us a little bit about yourself:

I live in Bristol, England, with my gorgeous husband, my dog, and two cats, and work at the University of Bristol in the Library Services. I love my day job, but my major passion in life is writing. I took an MA in Creative Writing at Cardiff University, and led creative writing workshops in schools. I’ve had a few poems, a paper, and a couple of articles published, but my main focus at the moment is writing my first novel, ‘Goodbye Horses’, a psychological drama about a woman living in self-imposed exile on the Shetland Islands, haunted by a dark secret. You can read some of my work on my website,

How long have you been using Natural Cycles for?

I’ve been using Natural Cycles since April 2017 as a method of contraception. I’m a pretty sceptical person – I need to see scientific evidence for everything! I did a lot of research before I started using it. The fact the app was certified and CE marked was incredibly reassuring and convinced me to give it a try. I’m so glad I did. It’s really easy to use – it only takes a minute or so each morning – and is amazingly accurate. I’m a bit of a data nerd, so I love seeing the variations in my temperature, the length of my phases, and how they compare to the average of other users. The little messages and reminders are great, and really useful; the app tells you the best time in your cycle to do a breast self-examination, for example, which is something I would never have remembered to do before. I feel like my whole adult life has been one long search for the right contraceptive, and I finally feel I’ve hit the jackpot with NC. It has given me so much insight into how my body works. We all learn the ovulatory cycle in school, but it all seems very abstract and a little intimidating, and somehow not applicable to real life. To learn about your own body, so easily, and in real time, is a massive eye-opener. I love feeling in tune with my cycle.

Would you recommend Natural Cycles to other women out there?

I would definitely recommend NC to other women, particularly if they’re struggling with other types of contraception. Read up about the app, research it yourself, give it a try. It’s been fantastic for me. It’s made me feel in control of my body and my fertility for the first time in my life.

A big thanks goes out to Beccy for sharing her story with us! We love hearing back from our lovely Cylers, everyone is unique and has their story to tell. We want to give women a voice so they can inspire others to get to know their bodies with Natural Cycles too – if you want to be a part of this movement go ahead and share your Natural Cycles story with us.

Looking forward to hearing from you, Your Natural Cycles team

Your Natural Cycles team

How to do a breast self-exam

Doing regular breast self-exams is something we feel every woman should be comfortable with as it’s a part of our overall reproductive health.

Which is also why we inform our Cyclers in the Natural Cycles app, when it’s best to do a breast self-exam. This will be shortly after your period, as your breasts are unlikely to be swollen and sore due to PMS symptoms. We send a message to women over thirty years of age automatically, as risk is increased, but everyone can set an automatic reminder in the app as they wish no matter what age.

This month is breast cancer awareness month, so we want to encourage you to learn how to do a self breast-exam and become more in tune with your body with our step by step guide on how to carry out a breast self-exam at home below.

This, of course, does not replace professional diagnosis and should you have any reason for concern, be sure to consult your doctor or gynecologist.

1.Visual mirror check

Begin the breast self-exam by stripping down to a bare upper body and taking a look at your breasts in the mirror.

Visually examine your breast in the mirror and check if:

  • Your breasts are their usual size, shape and colour
  • Check if there are any visual distortions or swellings. Some changes you might want to discuss with your doctor: dimpling, puckering or bulging of the skin, lumps, nipple distortion, fluid, redness, soreness not due to PMS, rash or swelling.

Also be sure to take a closer look at your armpit area as well by raising your arms overhead.

2.Examining with fingertips

You should examine your breasts with your fingertips, both while standing or sitting up and also whilst lying down flat on your back.

Tip: you might find it easier to do this in the shower as your skin is a little wet and slippery, or by using massage oil.

Use your opposite hand to feel your breast, so your right hand to feel your left breast and vice a versa. Keep your fingers straight and together, use the fingertips with a firm, smooth touch.

You can start from the nipple and move outwards in a circular motion and also use a more vertical up and down approach. Be sure to cover the entire range of your breast from your collarbone to the top of your abdomen and from your armpit to your cleavage.

If you notice anything don’t panic — 8 out of 10 lumps are not cancerous. For more information, you can visit this post is based on their information or speak to your doctor or gynaecologist.


Meet the team: Florence, the one taking care of our Cyclers

Every month we introduce a member of the Natural Cycles team, this time around it’s Florence – our Customer Relationship Manager. She makes sure that all of our lovely Cyclers are taken care of.

Where are you from?

I was born and raised in France but I’ve been living abroad for 10 years. I first moved to Barcelona in Spain just after my studies and after several years decided to go up north and moved to Stockholm. French is actually the language I use the least in my day-to-day.

Tell us about your work at Natural Cycles?

I am behind the emails & notifications the users of Natural Cycles get. From Newbies to Star Cyclers, from tips to reminders, I am working on sending tailored messages to help & inform the Cyclers, wherever they are at in their journey with us.

Why Natural Cycles?

Because working for a company that is a life changer and has such a positive impact for so many people is amazing. It is also super exciting to see how the product, the team and the company are growing at such a fast pace. The icing on the cake is that I get to work with topics that have always found interesting such as woman empowerment, misconceptions around female fertility, etc…

Favourite project at NC since you started?

I loved working on the reminders 😍.

What does it mean to be a good… CRM Manager?

It means, of course, many things, but empathy is the basis of all my work. If I couldn’t understand how and why our lovely Cyclers use Natural Cycles – it would be impossible to do my job.

What’s one thing you’ve learned during your time at Natural Cycles?

Wow, just one? When I started working at Natural Cycles I thought I was well informed about women’s reproductive health and the menstrual cycle. Well, after just a few days I realised that “I knew nothing”. It’s so many exciting projects going around in the office that I learn something new every day.

What’s your go-to place to eat in Stockholm?

I like to take people who come to visit Hermods, a vegetarian buffet in Södermalm with a nice outdoor area and an amazing view of the city. Perfect to watch one of the amazing sunsets of Stockholm.

Favourite feature in the Natural Cycles app?

As a user, I am quite addicted to the graph. But a message telling me that I have a nice temperature curve can brighten my day 🙂

Favourite song?

It changes a lot but lately it’s been “Ride” of Twenty One Pilots.

Favourite quote?

I never lose. I either win or learn.

Nelson Mandela

Tell us about your hobbies?

I discovered climbing 7 years ago and I recommend it to everyone. It’s fun, challenging and a great activity to do with your friends. Even if Sweden is not the best place for climbing, there are some very nice spots around Stockholm and great indoor climbing centers.


If you are interested in joining the Natural Cycles Team, working on improving women’s health, pushing the scientific research behind it and truly making an impact within the contraceptive and reproductive market – go ahead and check out our job openings here.

Cycler Story: “I’m more in tune with myself and my patterns.” – Anne

Thousands of women are using Natural Cycles every day and we love getting to know them and hearing their inspiring stories. This time around we had a chat with Anne who lives and works in London. She tells us about her adventures and how the app has helped her get in touch with her body and mind

Tell us a little bit about yourself:

I’m all about relationship building, whether in my personal or professional life! I work in employee comms, in an amazing startup in the center of London, and I love what I do! We’re all about building great relationships, helping companies be great employers, and facilitate everything in their relationships with their employees – I just can not imagine anything better I could be doing. Fantastic co-workers, great clients, wonderful work. Every day.

My other big passion is traveling and adventures. Or testing something new. Usually, something that scares me… a little. I’m French, but have lived in the US (7 years), Australia (6 months), Mayotte (2 years), Reunion Island (3 years), and now the UK (almost 2 years!) – so, in-depth exploring is one of my specialties. I’m also a big nature lover. Sometimes, nature’s strength and immensity scares me, but there’s something so beautiful about it. The same way I got interested in Natural Cycles, I am now more and more interested in my carbon footprint, and my diet and lifestyle (how about a plant-based diet?). Nature is something I love and cherish.

How long have you been using Natural Cycles for?

I’m still a Newbie! I’ve only been using NC for 3 full cycles now (and a few days), so I can’t say I really know it all! But it’s been the easiest process to get used to. I put my thermometer on my phone, so every morning there’s not even a chance of missing it. The few times I’ve missed is because I really couldn’t (on a flight, forgot my purse with it, etc.), otherwise I find it’s the easiest thing to do.

I think what I like most is the monthly temperature graph. For some reason, in the back of my mind, I was always ‘scared’ to be abnormal, or that something was wrong with me, because my mother received a lot of hormonal treatments before getting pregnant, and I somehow always assumed it would affect me. But this simple little graph, that shows the ups and downs, somehow really got rid of my fears, and made me realise: I’m actually okay and right now, everything looks fine! (Not saying that anything else wouldn’t be okay, but it’s nice to know there is nothing to worry about!) It makes me feel like I’m listening to my body, I’m more in tune with myself, my metabolism and my patterns. It’s so nice to feel the synchrony, that I’m not two separate entities, my brain and my body, but a whole system and now I’m finally listening to all of it, rather than trying to control it.

Would you recommend Natural Cycles to other women out there?

Absolutely! Some women are more open to this kind of method of course than others. But at the moment, I use it to learn more about my body and my cycle, as I think it’s the first important step for using this kind of method. I reckon that in a few months, I will start feeling more comfortable with my ‘green’ days. And maybe my boyfriend will be too. To be completely honest, I almost look forward to the other side of it, when one day I will try to become pregnant. Because then, I’ll know, really know, my body and its patterns. And that’ll be a huge advantage.

A big thanks goes out to Anne for sharing her story with us! We love hearing back from our lovely Cylers, everyone is unique and has their story to tell. We want to give women a voice so they can inspire others to get to know their bodies with Natural Cycles too – if you want to be a part of this movement go ahead and share your Natural Cycles story with us. Looking forward to hearing from you!


Your Natural Cycles team 

Enjoy this Cycler story?  You can read up on more of them here – ’cause everyone is unique.

Third and largest prospective study carried out on Natural Cycles

Ever since the beginning of our journey, one of our missions has been to lead the way when it comes to research in women’s health by conducting clinical studies within reproductive health. Which is why we’re beyond excited to finally share the news that we have published a third study together with leading experts in Women’s Health, once again confirming Natural Cycles’ efficacy.

This study was prospective, whereby real life data on the usage of the Natural Cycles app was analysed. Having studied over 22’785 women, who were 29 years of age on average, and analysed 224’563 menstrual cycles this is the largest prospective study carried out not only on Natural Cycles, but on natural contraception as of yet.

The publication confirms that under perfect use, when using Natural Cycles consistently and correctly, the app is 99% effective and under typical use, it is 93% effective.

A big thanks goes out to all of our Cyclers who have been a part of this journey and have contributed to the study through using Natural Cycles. We are thrilled that more and more women are choosing the app as an effective method of contraception. It is changing the way we perceive contraception in society and gives women a powerful tool to get to know their bodies better.

Let’s keep pushing, because progress starts with research.

You can read the full study here


Your Natural Cycles team

What happens during your menstrual cycle?

A menstrual cycle is simply the recurring process of preparing your body for a possible pregnancy. Possible being the word of importance here.  

It actually starts on the first day of your period and ends when your next one comes. A cycle usually lasts about 29 days on average but we are all unique and so is every cycle. Which is why it’s great to keep track of yours with Natural Cycles – you’ll know exactly how long your cycle is and it detects variations, no matter how small or big those might be.

Your cycle has two main phases, the follicular and luteal phase. These phases all drill down to hormonal changes in your body. Hormones are chemicals that pretty much control a lot of things in your body and its’ functions; from complex things like determining when you can get pregnant or not to whether you’re feeling particularly hungry or not.

What happens during the cycle phases?

Phase 1: ‘the follicular phase’.

This is when your body is preparing to ovulate i.e. release an egg from your ovaries. The days leading up to ovulation are your most fertile days and the risk of pregnancy is relatively high. Which is why they will always be red days in the app when you are preventing a pregnancy.

The follicular phase starts on the first day of your period, and ends when you ovulate. Your body temperature will remain lower during the first phase of your cycle. Which is one of the main indicators for the app to know what phase of your cycle you are in and why you have to measure your temperature every morning.

Phase 2: ‘the luteal phase’

This phase begins once you have ovulated. The egg survives 12-24 hours from the time it has been released. At the same time, a reproductive hormone called progesterone is released, which causes your temperature to rise. Your temperature will be higher in the second phase of your cycle.

Temperature is the main indicator Natural Cycles uses to detect that you have ovulated, but there are some other signs you are ovulating you might notice too.

If the egg is not fertilised by sperm, which can live for up to 5 days in the body, your progesterone levels will drop again. (An easy way to prevent the sperm from meeting the egg, is to use condoms.) The dropped levels of progesterone will also cause your period to arrive, and so your next cycle begins 😉


We are very excited to go into depth into the topic following months, so do go ahead and comment with any feedback you might have and let us know what you would like us to talk about more.

We’re all about educating because the knowledge that lies behind the menstrual cycle not only allows you to truly understand and believe in how Natural Cycles works but it gives you control.

So help us with this movement, go ahead and share this blogpost! #yourcyclematters

The importance of understanding your body and menstrual cycle #yourcyclematters

Over the past few years, we have learned that when it comes to reproductive health there is simply a knowledge gap and some myths floating around.

We believe it’s time to change all that. Because no matter whether you want to prevent or plan a pregnancy, everyone should know how their body and cycle works. By understanding your menstrual cycle, you truly know just how Natural Cycles works and why it’s an effective method of contraception.

Your menstrual cycle also plays a huge role in your health and by getting to know it you can make more informed decisions and take control. Which is why it’s our mission, to close this knowledge gap and educate, now more than ever.

Natural Cycles is not just about contraception, it’s about so much more. We hear that from our lovely Cyclers every day and their inspiring stories keep us pushing forward. They reflect that Natural Cycles is a powerful tool to get to know yourself, your body and menstrual cycle better.

From now on, we will be taking things back to basics and start openly talking about all things reproductive health so everyone can learn about it.

Sure we all have a period, but what about the stuff that goes on and we don’t see? Ovulation, cycle phases and hormones – we want you to understand it all so you can take control of your future.

So keep your eyes and ears peeled for the useful and fun knowledge we will be sharing on our social media channels, on the blog and in newsletters.

It’s time to start talking about reproductive health, fertility and the female body openly, start busting some myths and spreading the word to all women out there because #yourcyclematters.