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Is Daysy worth the investment? A 5-year review from a loyal user, Romy

You probably know them, the ladies who proudly share on Instagram and Tik Tok about their Daysy experience. Romy is one of them, she has been measuring for over 5 years and doesn't exactly hide her enthusiasm! Adding to this, Romy gives her Daysy review. She is a cycle expert and loves to help other ladies on their way fixing their menstrual cycle.

For fitfemaleacademy's online programme, Romy and Patricia got together on a Thursday morning in January (2024). Romy wants her followers to know all about Daysy:

  • What about its accuracy and scientific research?

  • How does it work and what does the device base the result on?

  • When are your fertile and infertile days?

  • How do your hormones regulate the menstrual cycle?

  • What does it take to ovulate?

Are you also orienting?

The video of this talk is well worth watching if you are orienting what options there are without continuing to use contraception like 'the pill', an IUD (also copper), shot pill, patch or ring.

Are you looking for:

  • How to accurately chart your personal cycle?

  • What if you want to avoid conception during fertile days?

  • Or you have a pregnancy wish now, or in the future?

  • In short, how to use Daysy in both situations?

Daysy studie 99,4% nauwkeurig in onderscheiden vruchtbare en onvruchtbare dagen

You are not fertile every day of your cycle!

During fertile days, you use a barrier method like e.g. condoms so that sperm cannot reach the ovaries in case you don't want to get pregnant. The Daysy® study we discuss in the video shows how low the error rate of Daysy® is. In short, this study looked at where is there still a small chance of conception where Daysy misses that. Did she indicate green light (infertile day) when it should actually be a red or yellow fertile day? Turns out that chance is 0.6% hence the smart internal algorithm in Daysy® is 99.4% accurate in distinguishing fertile and infertile days.

A false green day can be 6 days before ovulation day but that doesn't mean you have a 100% chance of getting pregnant then. The chance of getting pregnant at all on that day before ovulation is low 6.8%. So actually you could say that the actual margin of error of Daysy® is even lower.

If you look at the days after ovulation in the picture above, the chances of pregnancy are 0.8% and 0.4% during the 'buffer' days where you get red and yellow colours. So the situations where Daysy® indicated the green colour during specifically those days has a very low chance of an unintended pregnancy after ovulation.

The conclusion

  • Sperm can survive internally for up to 5 days.

  • Around ovulation, few days before, the chances of conception are highest.

  • Daysy indicates fertile days at least 5 days before the expected ovulation and wait with green light (infertile days) until the BBT (basal body temperature) is stably higher for several days, you are past the fertile window of your cycle.

  • Using a barrier method on infertile days is therefore not necessary.

Look at your Daysy in the morning after the reading to see what your colour is and you are ready to start the day!

volg je natuurlijke cyclus weet wanneer je zwanger kunt raken



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