Fertility tracker

What can I track in cycle tracking mode?

In this mode, the app gives you information about your daily fertility status, shows you days of high fertility and whether or when ovulation has been detected. 

You can track a wide variety of things such as period length, activity, sleep duration, mood or various symptoms. 

This makes our fertility tracker a companion in every situation and helps you to better understand your body. 

Can I use the femSense app as a period diary without a patch?

Naturally! Track your periods, fertile windows and enter how you feel in the app, use the femSense app to keep an eye on your cervical mucus, your weight or your sleeping behaviour. This gives you an overview of how your cycle behaves from month to month and allows you to adjust your lifestyle to your cycle and plan your everyday life accordingly. 

If you want the femSense app to be more personalised and accurate and you want confirmation of your ovulation, please visit ourWebshopand order your femSense patches. 

What can I track without the femSense patch?

The femSense algorithms use the cycle information you enter and statistical data to estimate your fertile days. This allows you to track your cycle and predict when you are fertile or when you will have your period. 

You can also use the app to track your cervical mucus or other symptoms. You can also enter things such as your mood, sleep duration or sporting activity and thus plan and organise your everyday life based on your cycle. 

If you want the femSense app to be more personalised and accurate and you want confirmation of your ovulation, then visit ourWebshopand order your first femSense patches! 

Is femSense suitable for contraception?

femSense can help to recognise days with high fertility and days with low fertility. 

femSense alone is not a form of contraception (and is not approved as such), but rather a tool that can be used in combination with other hormone-free methods to detect ovulation for the method of contraception. 

Under certain medical conditions, femSense cannot reliably measure ovulation. For more information, please seeWhen can femSense not be used?


What happens to my data?

Your body - your data. Your data is not our business model, as may be the case with other apps. We treat your data confidentially and never sell it to third parties. You can find out more in the Privacy policy on the femSense website.

Can I view my temperature curve?

femSense is not a medical thermometer and therefore deliberately does not display any temperature values. These could be misused, e.g. to measure fever. femSense is not intended to provide diagnostically relevant information.

The measured temperature data is analysed internally in order to determine the time of ovulation. The measured temperature data is not passed on to third parties.

Ordering and dispatch

Can I cancel an order?

You have the right to cancel your order within fourteen days of taking delivery of the goods. To exercise your right of cancellation, you must inform us of your decision by means of a clear declaration (e.g. by e-mail or letter). The unopened parcel must be returned to us immediately. The costs for the return shipment are to be borne by you.

Once we have received and checked the goods, we will refund you using the same payment method you used for the original transaction.

You can find more information on our website. Please add this Form with your return.

Who bears the costs for a return?

If the goods are returned within the cancellation period of 14 days, the buyer shall bear the postage costs.

Is femSense shipped in neutral packaging?

femSense is dispatched in a neutral shipping box. It is not possible to recognise the contents of the packaging from the outside. The box is very discreet and the sender of the parcel is SteadySense GmbH. 

In which countries is femSense available?

femSense is delivered to the following countries:

  • Germany
  • Liechtenstein
  • Luxembourg
  • Austria

Our partner delivers to the following countries Fleming Medical:

  • United Kingdom
  • Ireland

Our partner delivers to the following countries ToKaMedical:

  • Poland
How long does the delivery take?

Your order will be ready for dispatch within one working day. Delivery within Austria takes 1 to 2 working days, deliveries to other European countries take 4 to 7 working days.


Average duration (working days):

Germany: 4
Liechtenstein: 3
Luxembourg: 3
Austria: 1



Patch and communication

Can my weight affect the comfort of the patch?

The wearing comfort of the femSense patch can be affected if the patch is exposed to pressure or friction. femSense users with a high BMI occasionally report that their bra fits too tightly over the patch, which is not only uncomfortable but can also affect the functionality of the patch. For this reason, we recommend that users with a high BMI wear a sports bra or other comfortable underwear when wearing the femSense patch.

Can I do sports with the patch?

Of course, but as with any ordinary plaster, the adhesive strength can be affected by sweat/water/heat. However, this does not affect the technology inside the plaster.

How do I dispose of the patch?

The sensor installed in the femSense Patch uses a button cell battery as a power source and should therefore be disposed of in a battery recycling box.

You can also use our femSense Recycling concept use. If you return 6 patches to us, you will receive a voucher code for a free patch with your next order.

How many patches can I use per cycle?

You can use one patch per cycle. After applying and activating a patch according to the in-app instructions, the patch is linked to your current cycle.

If a problem occurs when wearing a patch, please contact our technical support (by email or use the "Contact support" function in the femSense app menu) before taking any further action.

Does the patch emit radiation?

No. Unlike other products on the market that have permanent data transmission (e.g. Bluetooth), the femSense Patch can only be read out via NFC (Near Field Communication). The femSense Patch only sends data for a brief moment when you hold your mobile phone up to the Patch to read it. The femSense Patch itself is completely passive and does not emit any radiation.

How often can I use the patch?

The patch is a disposable product and can only be used for one cycle. After removal, the patch can be disposed of in a waste battery collection container or you can contact our Recycling campaign participate. 

Can I shower, bathe or go to the sauna with the patch?

Of course you can shower while wearing the patch. The patch is designed so that daily personal hygiene is possible.

However, long baths, extensive swimming and saunas should be avoided, as the warm environment and water/sweat can reduce the adhesive strength of the patch (as with any other skin patch), which could cause it to come off prematurely.

How long does the patch have to be worn?

The wearing time is individual and depends on when we measure your ovulation - up to a maximum of 7 days.

Which smartphones does femSense work with?

Basically, the smartphone must have NFC and an internet connection in order to use the femSense app.

For Apple:

  • Apple devices from iPhone 7 or newer models can use NFC without restrictions. 
  • NFC is activated automatically, so you don't have to switch anything on or off. 
  • Note: iPhone 6s has NFC, but this is only available for Apple Pay.

For Android there are several ways you can check whether your smartphone has NFC:

  • Drag your status bar down and look for an NFC button there.
  • Open the settings and go to "Connections" or "Device connection" and look for a switch there to activate NFC
  • Visit the manufacturer's or dealer's website and search for the specifications for your device.

Get pregnant

Who is femSense suitable for?

femSense is suitable for women between the fertile ages of 16 and 49 who have cycles between 21 and 35 days and cycle length fluctuations of a maximum of +/- 3 days. 

The reliability of femSense may decrease with irregular cycles, so in this case you should consult a doctor before using femSense.

If you are currently undergoing hormone therapy, the accuracy of femSense may be impaired, as hormone preparations often also affect body temperature.

In addition, femSense cannot reliably determine your ovulation for some medical indications, you can find out more about this in this Contribution.

You can find more information on our website. Please add this Form with your return.

How does femSense help me get pregnant?

femSense helps you get pregnant by showing you exactly when you are most fertile and when you are ovulating.

Based on your cycle data, femSense determines the length of your cycle, your fertile days and when you should wear the patch in order to reliably determine your ovulation. The app's calendar shows you at the start of your cycle when you are most fertile. With the help of the patch, you can also see if and when ovulation has taken place.

To do this, the sensor built into the patch continuously measures your body temperature and uses your temperature data to analyse whether ovulation has taken place.

The femSense app's intelligent algorithms adapt individually to your cycle and temperature profile and become more precise the longer you use femSense.

In "Get pregnant" mode, the 4 most fertile days are marked with hearts in the app. The app tells you the perfect days to get pregnant and when you ovulate - the rest is up to you!


How does femSense work if you want to have children?

femSense is a new form of basal body temperature measurement that works completely automatically. The femSense system consists of a skin patch with an integrated temperature measurement chip. This plaster (also known as a patch) is applied under the armpit and, once activated, continuously measures your body temperature for several days.

The patch should be read at least twice a day to obtain new information every day. Based on the recorded data, femSense recognises your ovulation and also tells you when you are most fertile. The app reminds you when to stick the patch and indicates when you are particularly fertile.

How exactly is femSense?

The temperature sensor used in the femSense Patch detects temperature differences of less than 0.1 °C and is specifically designed to detect the minimal rise in basal body temperature caused by ovulation, which is normally between 0.2 °C and 0.5 °C.

Unlike simple basal thermometers, the patch continuously records temperature data several times an hour. The femSense app notifies you as soon as it has detected your ovulation. No more tedious recording and analysing!

femSense is a CE-certified medical device manufactured in Austria.

Medical indications

Which ingredients are used in the patch?

The materials used are acrylate-based. The adhesives of the materials that come into contact with your skin are latex-free and tested for biocompatibility. The materials to which the adhesives are applied are polyethylene (PE) films or foams and a non-woven fabric.

Despite the utmost care in the choice of materials, localised skin irritation can occasionally occur. People who are generally more sensitive to plasters are more likely to be affected.


When can femSense not be used?

femSense cannot reliably measure ovulation in certain medical conditions. These include

  • Serious, acute or chronic illnesses
  • Nicotine, alcohol or drug abuse
  • Oligomenorrhoea (irregular menstrual bleeding)
  • Polycystic ovary syndrome (PCOS)
  • Severely overweight or underweight
  • Hirsutism
  • Hormone treatment
  • Allergy to plaster components
How does femSense measure my ovulation?

femSense uses the widely used temperature method and brings it into the 21st century to determine your ovulation. Immediately after ovulation, your body temperature starts to rise by a few tenths of a degree centigrade. This minimal temperature rise can be difficult to detect with conventional thermometers and it often takes several days to get a result. femSense is able to detect this temperature rise as it occurs through continuous temperature measurement. Unlike single temperature readings taken once a day, femSense algorithms use hundreds of temperature readings to confirm your ovulation.

Why does femSense show a different ovulation day than my ovulation test?

Ovulation tests are used to determine when you are ovulating and when you are most likely to conceive. As different methods for determining ovulation measure different body signals, they are "positive" on different days. 

Ovulation tests measure the concentration of a hormone that indicates that the body is preparing for ovulation. femSense continuously measures your body temperature and can therefore determine the temperature rise that occurs after ovulation. The femSense app can estimate the start of your fertile days and the femSense patch measures and confirms your ovulation. 

In short: ovulation tests confirm that your body is preparing for ovulation. femSense confirms your fertile days and your ovulation.

You can find more information about femSense and ovulation tests here: Why femSense and LH tests show different results - and that's OK


Can I use femSense for PCO?

femSense has not been tested for women with PCOS. femSense is most reliable for regular cycles with a length between 21 and 35 days and a maximum deviation of +/- 3 days.

The algorithm relies on previous cycles to predict your fertile window and the patch is only worn for a maximum of 7 days during this time. If the patch has not measured ovulation during this time, the app will notify you and ask you to remove the patch. This means that if you have a very long cycle after a few shorter cycles, the app could predict your fertile window too early and the patch would not measure your ovulation.

Unfortunately, this means that we cannot recommend femSense for women with PCOS and therefore an irregular cycle.

However, we have had several clients with PCOS who have had periods of regularity where femSense worked. Therefore, we say that we cannot recommend femSense for PCOS, but every woman is an individual and even PCOS seems to be individual!

Can femSense be used for irregular cycles?

femSense is most reliable for cycles with a regular length of between 21 and 35 days. The reliability of femSense decreases with shorter or longer cycles. If you have very irregular cycles (a regular deviation of more than +/- 3 days), we recommend that you consult your doctor before using femSense. 

You can find information about femSense and PCO/PCOS here: Can I use femSense for PCO?

My skin is allergic to plasters, can I still use the femSense patch?

The femSense patch consists of hypoallergenic plaster materials that are used in medical wound care. Nevertheless, the components of the plaster materials can cause irritation on sensitive skin. Symptoms such as itching, burning, redness or slight skin swelling may occur. In this case, please remove the plaster and apply a soothing ointment to the area. 

If you are unsure whether femSense is suitable for you, please contact your doctor or register via e-mail support@femsense.com with our technical support.


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