2023 05 02 lh with femsense title

The combination of femSense with the LH test

Adding LH test results to the femSense app can not only help you to determine your fertile window more accurately, but also to learn more about the female cycle.

As part of the further development of the femSense app and the preparation of femSense contraception, we are collecting information about the LH surge and how it relates to each individual woman and her ovulation. By adding this additional information to our algorithm, we can more accurately predict a woman's fertile window and increase the reliability of the femSense system.

Ovulation is a process and not an instantaneous event

Ovulation is a complex process that takes up to 24 hours, but the body prepares for ovulation for even longer. In your ovaries, tiny eggs develop in vesicles called follicles, which are released during ovulation. The body knows it's time to release an egg when oestrogen levels peak during your menstrual cycle. The brain produces a surge of luteinising hormone (LH), which triggers ovulation.

This LH surge normally occurs 24 to 48 hours before ovulation and traces of the hormone can be detected in the urine. The LH ovulation tests react to this. After ovulation, the progesterone level rises, which also causes the body temperature to rise. It is precisely this tiny rise in temperature that femSense can detect. The temperature rise is a direct result of ovulation and therefore only the temperature method can confirm ovulation. Once ovulation has taken place, you are fertile for about 24 hours.

The steps of ovulation

- The oestrogen level reaches its peak, which leads to an increase in the LH level

- Ovulation begins and a follicle releases a mature egg cell

- After ovulation, the empty follicle turns into the corpus luteum

- The corpus luteum causes progesterone levels to rise

- Higher progesterone causes the body temperature to rise

While ovulation test strips measure the presence of LH (luteinising hormone) in the urine as an indication that the body is preparing for ovulation, femSense uses the temperature method to measure and confirm that ovulation has taken place. In other words, the LH test measures the beginning of the fertile window and the temperature method measures the end.

How adding LH test results (OPKs) helps me
to the femSense app at the
Determination of my
fertile window?

LH tests, also known as OPKs (for Ovulation Predictor Kit), are commonly used to predict ovulation. OPKs indicate that LH levels are rising and that the body is preparing for ovulation. LH ovulation test strips measure the concentration of LH in the urine, which rises when the body is preparing for ovulation. Most OPK strips look and work like home pregnancy tests: you pee on a test strip and wait for the lines to appear. A positive result means that your LH level is rising and you can expect to ovulate soon. A rise in LH levels indicates that the body is preparing for ovulation and you are entering your fertile window. A positive LH test is therefore a good indication of the start of your fertile period.

femSense uses the temperature method to measure and confirm that ovulation has taken place. At the time of ovulation, the woman's basal body temperature rises by a tiny amount and remains slightly elevated in the second half of the cycle. This tiny rise in body temperature is therefore a direct result of ovulation and a reliable indication that ovulation has taken place. If ovulation had not taken place, there would be no rise in temperature. This means that the temperature method recognises ovulation after it has taken place. In fact, the temperature method is the only "home test" that can confirm ovulation.

In short, LH tests measure the rise in hormone levels BEFORE ovulation, while femSense uses the temperature method to determine the temperature rise AFTER ovulation.

How can the addition of LH test results
to my femSense app
the accuracy of the femSense
Improve the algorithm?

We are constantly updating and improving the femSense app and, of course, the underlying algorithm for predicting the fertile window. Although an independent Swiss statistics institute recently confirmed that femSense achieves an accuracy of 99.73% when predicting the fertile window, we still see room for improvement. Especially if femSense can soon be used as a contraceptive method. That is why it is now not only possible to enter the LH test results in the app, but we even recommend it! This way, our algorithm can "learn" more about the menstrual cycle and make even more accurate predictions. A woman's cycle is more than just her period, it's a fluctuation of hormones that affect you both mentally and physically.

The more we learn about women's menstrual cycles, the better we can understand and support their reproductive health - and YOU can make a contribution! Anonymously and privately.

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How can adding
my LH results for the femSense app
benefit other women?

Thanks to technology and research, we now know more about the complex hormonal changes that take place during a woman's menstrual cycle. This has contributed to the development of innovative new products such as the femSense sensor patch, ovulation prediction kits (OPKs) and fertility monitoring apps. These products help women to understand their menstrual cycle and find out when they are most likely to conceive. By offering these services, we can empower women to take control of their reproductive health and make smart family planning decisions. However, there is still a lot to learn!

Research on women's health and their menstrual cycle has been woefully inadequate. However, we now have the opportunity to gather information and improve our understanding of these issues. By using femSense patches and tracking LH levels, we can gain insight into the fertile window and ovulation, information that can be used to educate women about their fertility and improve their reproductive health.

You too can be part of this revolution, anonymously and privately. Simply enter your LH measurements into the femSense app while wearing the patch. This helps us to narrow down the fertile window, but also to learn more about the process of ovulation. From the LH surge, signalling that the body is preparing for ovulation, to the rise in basal body temperature, confirming that ovulation has taken place.

Together we are stronger! Thank you for your support!

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