femSense in comparison with other methods for determining ovulation 


e at femSense have given the temperature method a level-up and brought it into the 21st century. Why? Because we think it's the best way to naturally monitor your cycle and determine your fertile days to successfully get pregnant. Let's take a closer look at why you should rely on the femSense temperature method 2.0 and how it compares to other ovulation tests.

How the femSense app calculates your fertile days

FemSense is your game changer when it comes to knowing more about your own fertility and understanding your cycle better. You are not fertile every day of the month and don't have the same hormonal requirements every day, as the female cycle is a complex sequence of hormonal processes that we have already analysed in terms of Sport, yours Energy level and your nutritional requirements have looked at.

But let's start at the beginning: femSense consists of the free cycle tracking app of the same name and the smart patches with an integrated temperature sensor. In order to determine your fertile window, you first need to enter your last cycle data, i.e. when your period started, in the app. The more data you have, the better. Why? Our algorithm receives more data points and can therefore predict your fertile window and the date of your next predicted period more accurately. Because even if the female cycle is "on average" 28 days long, it is not possible to make any generally valid statements about this, as every woman's cycle is highly individual and the average cycle length can range between 24 and 38 days. Only around 10% of all women have a cycle that lasts 28 days.

Did you know? Our app can predict your fertile window with a certainty of 99.73%, which has been tested in an independent study.

So as your fertile window and ovulation approach, our second product, or as we affectionately call it, our little superhero, the smart sensor patch, comes into play. Important: You only apply the patch when the app prompts you to do so, as it determines your patch application day for you. A big misconception when it comes to our patch is that many users believe they have to wear our patch every day. But that's not true. You only wear it on your fertile days until your ovulation has been detected and on a maximum of 7 days per month.

What does the femSense patch do?

You stick the femSense patch about 4 fingers wide under your armpit, but the app guides you easily through the application using a tutorial. Once attached, the smart patch now continuously monitors your body temperature. Why does it do this? There is a direct correlation between the rise in your body temperature (basal body temperature) and your ovulation. After you ovulate, the release of the hormone progesterone ensures that your body temperature rises by a few tenths of a degree (only around 0.2°C to 0.5°C). This is a sure sign that your ovulation has taken place.

The smart femSense Patch measures this post-ovulatory temperature rise without the risk of making mistakes in the measurement, as is the case with the manual, conventional temperature method. For example, you have to take your body temperature manually every day immediately after waking up while still lying in bed. This is very error-prone, as the measurement has to be taken at the same time every day, you have to keep records yourself and external factors such as stress or alcohol can also influence the measurement. With femSense you are safe from such application errors. You simply read the temperature twice a day (regardless of the time) with your smartphone and transfer your temperature data to the app.

This works using NFC technology, which you are already familiar with from cashless payments or electronic passports. The app then analyses your temperature data and tells you in seconds whether you have already ovulated or whether you still need to keep wearing the patch. If your ovulation has been recognised, you can remove your patch immediately afterwards. If femSense does not detect ovulation, you will also be asked to remove your patch after 7 days, as you should not wear it for another week. Did you know? Anovulatory cycles, i.e. cycles without ovulation, are completely normal and every woman has cycles without ovulation once or twice a year on average. So even if femSense doesn't detect ovulation, there's no need to worry.

Why you can trust femSense

Our sensor patch is an approved medical device, which is subject to a large number of requirements and specifications. With us, you get a thoroughly tested and researched product that you can rely on. We have also developed the product together with biomedical specialists and fertility experts and many gynaecologists recommend femSense to their patients who are trying to conceive.

FemSense compared to other methods for determining your ovulation

To put femSense into perspective with other methods of determining your ovulation, we have compared femSense with the conventional temperature method, ovulation strips (LH tests) and cycle tracking apps. If you want to know more about how LH tests predict your ovulation and how they differ from temperature measurement methods, we can offer you this article recommend.

As you can see, with our femSense complete package you get a wonderful and reliable tool for tracking your fertility! Would you like to test femSense without obligation? Sign up for our newsletter so that you don't miss any more news and save 10% on your first order! You can also follow us on our Instagram account, to make sure you don't miss any more news.



McLaughlin (01/02/2024), Menstrual cycle.

Johnson, Marriott and Zinaman, (01/02/2024), Can apps and calendar methods predict ovulation with accuracy?

Su HW, Yi YC, Wei TY et al (01/02/2024), Detection of ovulation, a review of currently available methods

Steward, Raja (01/02/2024), Physiology, Ovulation And Basal Body Temperature.

Tina is the Marketing Manager at femSense and firmly believes that great things happen when women support and empower each other, because in this "men's-world" there clearly needs to be more sisterhood. She lives in harmony with her superpower aka her cycle and writes about all the topics that matter.

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