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Daysy has been developed as a medical device.

Precision and quality

Femtech boutique is an online store created to propose eco-friendly and tech-savvy choices for women. We propose solutions which can reduce waste and help women to be conscious of their menstrual cycle and health. We are based in Tallinn, Estonia. The orders are sent out from our warehouses in Tallinn. We use Omniva, Itella and DPD parcel machines to deliver our products which makes it easy to order from the Baltic states.

How is Daysy being created ?

Switzerland-based Valley Electronics AG, creator of Daysy, is certified according to EN ISO 13485, meaning that our quality management is oriented toward the latest standards for medical products. All procedures at Valley Electronics AG are regularly subjected to internal and external overview. This allows us to continuously improve on and innovate our family of fertility trackers. Valley Electronics AG is registered with the FDA and is required to comply with medical device regulations that are subject to regular inspections by the FDA in our Zurich office and suppliers.

Furthermore, our quality management system is audited yearly by an independent European Notified Body. Our goal: accuracy and quality Valley Electronics AG is a pioneer in the field of fertility trackers. We have developed, innovated, and improved on fertility tracking technology for over three decades. We have 500,000 users worldwide who can attest to the accuracy and quality of our devices. We have history and longevity, but we are also on the cutting edge of femtech for fertility. Daysy was the first fertility tracker to be combined with a companion app. Our updated tracker, Daysy 2.0 is the 2019 winner of the Red Dot Design Award.

The Fertility Tracker Method is based, in part, on the Calculothermal Method and consists of a combination of three elements:

The recording and learning of new data (the daily basal temperature, the beginning and end of menstruation, as well as the collected historical cycle data) by a Fertility Tracker. The statistically significant evaluation of the post-ovulation temperature rise, with current and historical data from the database, by an algorithm adapted to the female cycle. – The avoidance of human input and interpretation errors through the combination of hardware (the sensor) and software (the algorithm) in one device (the Fertility Tracker). The first Fertility Tracker was developed by Dr. Hubertus Rechberg in 1986. His company Valley Electronics continues to develop and innovate Fertility Trackers worldwide, including the Pearly, Lady-Comp, Baby-Comp, and Daysy. We strive to create the best fertility trackers on the market and be a leader in our industry. That is why we continuously work to optimize Daysy. We always endeavor to find the best solution for our users. Going forward, we will continue to spare neither cost nor effort to make sure that you are always happy with Daysy.

The unique Daysy algorithm

Daysy determines your fertile and infertile phase using an extensive database and proprietary algorithm. Based on five million menstrual cycles and an algorithm that draws on knowledge from more than 30 years of research, including several studies, Daysy can give you reliable information about your menstrual cycle. The accuracy of the algorithm used by Daysy has been systematically tested.

For the scientific study, 107,000 cycles (basal temperature, menstrual input) of 5,328 women from Germany and Switzerland were evaluated over a period of ten years. The independently reviewed result shows that Daysy has an overall accuracy of 99.4% in the calculation of infertile (green) days. Independently verified results show that the accuracy of Daysy’s (green) days calculation is 99.4%.

For more Information please click:
Daysy Clinical Trial 2021
Fact Sheet Study Just 0.6% of the days displayed were green, although they were in the fertile window and thus should have been “red” (possibly fertile) (see graph).

However, 50% of these “false green days” were five days before ovulation and thus have only a minimal chance of pregnancy during this period. 2) statistical analysis (for example, temperature increase after ovulation).
The algorithm is created by combining two elements – the acquisition and learning of new data (your daily basal body temperature, start and end of menstruation, and accumulated past cycle data) and statistical analysis (e.g. the temperature rise that occurs after ovulation). After a learning period, during which Daysy gathers your personal data, the algorithm begins to predict your ovulation and can open your fertile window (red days) at least five days before the earliest possible date of ovulation
next menstruation.

Once a rise in basal body temperature is registered and the algorithm can confidently recognize ovulation, Daysy will show you subsequent individual infertile (green) days until the next menstruation In the background, the algorithm takes into account the previous average temperature for each measurement, so it is also possible to tolerate occasional outliers or measurement failures.
If Daysy does not have sufficient data to deliver a red (possible fertile) or green (infertile) indicator, Daysy will display a yellow (learning/cycle fluctuation) indicator and remember the fluctuation for the coming cycle.

In short, Daysy learns!
Tracking BBT: a few degrees make the difference Daysy uses a very sensitive sensor to measure the basal body temperature. The sensor’s most unique feature is that it waits for the mean temperature value, which can take up to 60 seconds.

The sensor warms up before it records your basal body temperature in order to receive an accurate result. Daysy waits until the final temperature value has stabilized to complete the reading. If the temperature drops during the measurement (for example, due to cold air that gets into the mouth through breathing), the sensor waits for it to rise again and stabilize. This unique feature differentiates Daysy from less sophisticated basal body thermometers.

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