If you’re already excited about the Daysy Fertility Monitor, click here to get one and automatically get $15 off!

The “femtech” space is blazing (to the tune of $50 billion by 2025), and there is no shortage of innovative products that are literally changing the way women manage their periods and fertility.

It is indeed an exciting time to be a person with a period, amiright?!

One such device is Daysy, a menstrual cycle and fertility monitor. Finally, a powerful tool that fits neatly in the palm of your hand, and accurately tracks proven signs and symptoms of fertility on a day to day basis. Paper tracking charts have never seemed so old-school as they do now lol!

Daysy Fertility Monitor - The digital fertility monitor with the simple color system

I’ve got to admit, I was super skeptical about the Daysy before I started using her. I’ve been charting my cycle using my basal body temperature and cervical fluid patterns for about ten years, so relying solely on a teensy device to tell me when I am fertile/not fertile was mildly terrifying!

I know the “fear of pregnancy” struggle is VERY real for every woman who is on hormonal birth control or on a non-hormonal IUD, so I’m pumped to share about this amazing device with all of you!

Daysy Fertility Monitor

PS. I’ve got a special discount for any of you babes who want to get your hands on a Daysy. Click here to purchase your very own Daysy and get an automatic $15 off!

The Quick and Dirty:

Daysy is the real deal people and I have no doubt she will turn you into a cycle tracking and fertility ninja in a very short period of time.

You can start using your Daysy the first day you receive her. She gives you clear signals, via different colored lights, about whether you are fertile or not fertile.

  • Yellow – learning phase/caution days
  • Red – fertile days
  • Green – safe/infertile days
  • Purple – menstruation days

Note: if you have been using hormonal birth control, you must stop using it before starting to use Daysy.

You don’t have to measure your temperature at the same time every day, which is super helpful for people who wake up at different times on different days. You just have to make sure you take your temp right after waking up.

As a reminder to take your temp, you can set an alarm on DaysyView, which is the app that accompanies the Daysy device.

Daysy Fertility Monitor - Nicole Jardim

Here’s what my app looks like for the past three months. I started using the device in May so I had quite a lot of yellow days while Daysy was “learning my cycle,” but as you can see for June and July, those practically disappeared. Daysy is smart, and a quick learner! 🙂

Daysy Cycle Tracking

A’s to your Q’s

I had a chat with my girl Holly Grigg-Spall, author of Sweetening the Pill, and knower of all things Daysy, and she answered the big questions on my (and every woman’s) mind.

NJ: How does Daysy actually work? (I’d love details on the technology, algorithm etc). How does it work without simultaneously tracking your cervical fluid.

HGS:  Essentially Daysy contains a computer, a database of millions of cycles and their data. When Daysy is learning your cycle she compares that unique new information to the database of information to determine when you have ovulated. Once you have enough cycles inputted, she starts to compare your new information to past information on your own cycles to make judgments about when you ovulate. The fertile window is started by calculating the earliest point you could ovulate based on your cycle history and based on the database information.

NJ: I read the little pamphlet that came with the Daysy from front to back, and it says that it is not to be used for contraception! Can you address this?

HGS: The FDA put a lot of pressure on the company to not call Daysy a contraceptive device or a birth control device when they first brought it to the US. They have strict definitions about what can be called contraception so Daysy’s official description of their product is that it’s “for planning and preventing pregnancy.” The accuracy of 99.3% is for planning or preventing pregnancy – so you don’t say “99.3% effective” like you would with a contraception like the pill or IUD.

NJ: How is the Daysy device different to a basal thermometer and practicing the Fertility Awareness Method?

HGS:  The main thing is that Daysy does the interpretation for you. You don’t chart. You don’t need to study or learn anything to start using Daysy effectively (although many women get curious and will start reading up and taking classes). Daysy tells you whether you’re fertile or infertile, it doesn’t involve analyzing a chart or asking a practitioner for advice.

NJ: How long does it take for Daysy to get to know your body’s unique cycle?

HGS: Daysy is accurate out of the box, but she takes about 3 months to learn your cycle. So you will get yellow (learning phase/caution days) and red (fertile days) more-so in the first 3 cycles entered. Most women get some green (non-fertile, safe days) once they enter first menstruation within a cycle and a half.

Then it builds up – they get more and more green days the more data they enter (the more temps they do). In the end, if you temp every day (missing temps means more yellow days) you will likely get about 8-9 red days per cycle.

Daysy is usually more conservative in readings when compared to charting manually with a BBT thermometer and app or paper chart. So if you chart manually following all the rules outlined in Taking Charge of Your Fertility (a must-have book about charting your menstrual cycle using the Fertility Awareness Method), you might be able to get down to 7 fertile days per cycle (or 7 red days, in Daysy language). Some women will get 7 red days with Daysy if their cycles are super regular, otherwise they will get 8 or 9 as a buffer.

It’s comparable to being told to practice manual charting for 3-6 months before using it to prevent pregnancy.

NJ: Does Daysy work for women with amenorrhea and/or irregular periods? PCOS?

HGS: Many women who have a PCOS diagnosis or have irregular periods use Daysy – however, they do get more red/yellow days than women with regular cycles and regular ovulation.

Women with PCOS say they like that it gives them a clear indicator of when they *do* ovulate. Manually charting with PCOS can take a lot more determination and persistence than it does for other women, so women with PCOS definitely find the Daysy to be helpful. Other women may want to check cervical fluid instead so they can better plan pregnancy, or have more unprotected sex than Daysy alone would recommend.

HOWEVER – we don’t recommend women with extreme fluctuations use Daysy – if one cycle is 30 days, the next 50, the next 65, the next 35 and so forth. If they have a range of time they can rely on that covers like a week, for instance 25-32 days long or 33-40 days long, that’s okay. Daysy is suitable for cycles with a range up to 40 days long.

The only time we have heard of someone being in that 0.7% and getting pregnant on a green, safe day (so it was a device error not a user error) – is when a woman had ovulated extremely early in comparison to her past 18 or more cycles. Late ovulation will just incur more red days. Super early ovulation randomly is a problem. But only one woman has reported this. All other reports of pregnancy when trying to avoid with Daysy have been user-error – failed barrier, unprotected sex on a yellow day.

We tend to advise women with irregular cycles to get their cycles as regular as possible to get the most out of Daysy, and point them to someone like you! Then they get more green days and the experience is better, plus they feel better!

For Amenorrhea – Daysy won’t give you any green days until you actually menstruate.

NJ: Does the Daysy work for someone who has recently given birth and is breastfeeding?

HGS: Daysy is very popular with new moms because you only need 3 hours of consecutive sleep and you don’t have to take your temp at the same time every day. However, Daysy won’t know when you first ovulate. She will start giving you green days after you enter first post-partum menstruation. Prior to that it will be all be yellow and red. So you can get into the habit of temping, but to be extra conservative there will be no green days til both first ovulation and first menstruation have past. This video might help: https://www.youtube.com/watch?v=OjuqJreVwbQ

NJ: How accurate is Daysy as a method of predicting your fertile window?

HGS: It’s 99.3% accurate – based on annual testing as a certified medical device. But we don’t say “effectiveness as birth control” because of FDA rules. It’s accurate for planning or preventing pregnancy – meaning the readings it will give (green, red, yellow) are 99.3% accurate.

NJ: Can Daysy be used for achieving pregnancy as well as avoiding pregnancy?

HGS: Yes, again with 99.3% accuracy. It can be used for either. It’s classed as a “fertility monitor” for this reason.

So what do ya think?? If there are more questions or concerns, just comment below!

As you can probably tell, I’m psyched about the Daysy and the fact that this little device has the power to alter the current birth control and fertility tracking landscape. As in, if you don’t want to take the risk of being on hormonal birth control, or you don’t want a copper IUD in your uterus, now you have another option.

Daysy really is the solution for women who are scared to come off of hormonal birth control and worried about how to figure out the whole “cycle tracking” thing. On the flip side, it’s a fabulous option for women who really want to learn more about how their body functions and understand their unique menstrual cycle.

Special discount for all my readers!

Don’t forget, I’ve got a special discount for you. Click here to purchase your very own Daysy and get an automatic $15 off.