Follow your monthly cycle with the menstrual cycle tracker Daysy

Get to know your cycle with Daysy!

Your monthly cycle is your best friend when it comes to finding out when you have to use contraception. Did you know that every woman can only get pregnant during a few days of her cycle? After ovulation , the egg can be fertilized for a maximum of 18 hours. But the fertile days begin up to five days before ovulation, because that‘s how long your partner's sperm can wait for the egg inside your fallopian tubes. That also means that on many days of your cycle, you cannot get pregnant at all.

Once you know your own fertile and infertile phases, you can decide to avoid intercourse on fertile days, or use a barrier method such as a condom or a diaphragm. A manual calculation of your own fertility through a combination of the temperature method and an analysis of your cervical mucus is possible, and can, with a little practice, be very precise. But it requires a lot of your time and the commitment to work very meticulously. If your days are stressful and you are looking to save time, we have an excellent alternative for you: Daysy.

Daysy menstrual cycle tracker: This is how it works!

Daysy is a highly modern cycle tracker that can calculate your monthly cycle with an accuracy of 99.4%, using just your morning basal temperature and a proven algorithm that has been developed over decades.

In order for Daysy to have all the information it needs to track your monthly cycle, all you have to do is take your morning basal temperature . Place Daysy's highly sensitive test prod underneath your tongue every morning before you get out of bed. Wait for 30 to 60 seconds for a beep to indicate that the measurement has finished. Push a button to confirm that you are currently menstruating if that applies, and right away, the result is displayed to you as a colorful light: red means fertile and green means infertile. On red days, you should use a contraceptive such as a condom or a diaphragm when you are having sex and want to avoid a pregnancy. On green days, you have a green light!

Daysy has an app: DaysyDay helps you to plan your free time

In addition to the fertility display on your cycle tracker Daysy, you can use the free app DaysyDay. Install DaysyDay on your smartphone and synchronize it with Daysy. The app lets you access a preview of next month’s fertility and adjust your free time activities such as going swimming. You can also complete your personal cycle calendar by adding your own notes.

Let Daysy track your monthly cycle for you, and use contraceptives only when required for a life in harmony with your body’s natural rhythm.

What is the best way to measure?

For optimal use of Daysy, we recommend that you should have slept sufficiently (at least one hour) before the measurement. It is important that you take your temperature immediately after waking up, before getting up and becoming active. Measure below your tongue, with your mouth closed, and keep the device steady while it is measuring. Video Tutorial

Do I have to measure at the same time every day?

No. You should have at least one hour of good quality sleep before the measurement. It is important that you take your temperature immediately after waking up, before getting up and becoming active. For optimal use of Daysy, try to get at least 3 or more hours of sleep before measuring. Less sleep can result in more temperature fluctuations causing Daysy to give more fertile or potentially fertile days.

How do I enter or edit menstruation?

You can confirm or remove menstruation at any time during the current day. Simply press the button to turn on your Daysy, and then press and hold the activation button until the violet light lights up without flashing and you hear a "beep." Confirm you are menstruating for each day of active bleeding and for a minimum of three consecutive days. You can also remove menstruation data for the same day by turning Daysy on and pressing and holding the activation button until the purple/blue light is no longer solidly lit and begins flashing again.

Video Tutorial

How long until Daysy knows my personal cycle?

The first 2-4 cycles of use are considered Daysy's learning phase. Over the course of her learning phase, Daysy will come to understand your cycle and begin narrowing down your fertile window. Daysy remains quite cautious and conservative during this time, which is why Daysy is accurate starting the very first day.

When can I start to rely on Daysy's results?

You can rely on Daysy's results starting the very first day of use. In the beginning, you will see more yellow and red days because Daysy is still learning your unique cycle. You will see more green days as Daysy comes to understand your cycle and can narrow down your fertile window. The more regularly you measure, the better.

My cycle is irregular. Can I still use the devices?

Yes. Irregular cycles are not a problem for Daysy/Lady-Comp. Even with irregular cycles, all Valley devices distinguish between non-fertile and fertile days with a very high accuracy. However, in case of extreme fluctuations between cycles it will give you more red and yellow lights and less green lights. Fluctuations of several days are usually not a problem. If you have questions about your unique cycle, please reach out to our team of experts.

Are there any costs associated with the DaysyDay app?

No! DaysyDay is free! There are no in-app purchases or upgrade fees.

Does illness reduce the reliability of the device?

In general, you should skip measurements during illness and while you are taking medication that can have an influence on your body temperature or cycle. If you have doubts, contact your doctor or our customer service team.

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Get more information

Everything you need to know about the menstrual cycle: phases, function and significance for your health

Find more about the factors that can influence your menstrual cycle.

Learn why the commonly assumed 28-day cycle doesn’t apply to most women.

Further articles on the topic of Menstrual Cycle in our adviser:

Menstrual cycle calculator