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natural cycles vs daysy vs ava fertility - which is best

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Natural Cycles vs Daysy vs Ava: Which Fertility Tracking App Is The Best?

About the Author

Jane Feddersen

Jane is a former DI student-athlete and lifelong health enthusiast. Since graduating from College of Charleston where she played both indoor & beach volleyball, Jane’s spent the last four years building her marketing career with experience in project and partner management. Outside of work, her nutrition certification, dog, travel and yoga flows keep her busy.

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About Dr. Steve Kim, MD

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Dr. Kim received his BA in Human Biology at Stanford University, before receiving his M.D. degree (Primary Care Track) from UC Davis School of Medicine. He completed his Internship & Residency in Family Practice from Glendale Adventist Hospital and is Board-Certified in Family Medicine via the American Board of Family Medicine. He has held faculty appointments at Stanford & UCSF medical schools and has championed telemedicine for decades. He is also a decorated, retired Flight Surgeon from the US Air Force Reserves.

In this Article

In this Article

Jane Feddersen

For a long time, fertility has been an expensive, taboo topic to dive into. More recently though, women are opening up space to talk about their fertility journeys, especially in the wake of overturning Roe vs Wade. 


Companies like Ava, Daysy, and Natural Cycle are introducing new ways to track fertility. Moving away from birth control pills, these digital fertility trackers offer an all-natural hormone-free birth control by helping you to get clued in on your fertility window and ovulation days.


Not everyone is interested in fertility tracking for the same reason. 60% of women are looking to fertility tracking methods to prevent pregnancy, others are hoping to use these tracking methods to help them get pregnant, and some just simply want to understand their menstrual cycles on a deeper level. 


Instead of shelling out thousands of dollars and tons of time with doctors’ appointments, these women’s fertility tracking health startups have found ways to make fertility tracking something that can be done at a much lower cost, accurately, more naturally, and on your own time. Because let’s be honest, these days, we’re all about that instant gratification. 


Curious about fertility tracking accuracy or worried about your personal data being weaponized against you in the wake of overturning Roe v Wade? Let’s dig a bit deeper into these three fertility tracking apps – Natural Cycles vs Daysy vs Ava – to see which is the best fit for all of your fertility needs. 


TLDR: Which fertility tracking app do we recommend?


Short on time? Here are our top recommendations:


Choose Natural Cycles if you want a budget-friendly option with all the features of other competing apps. They are also one of the leading apps working on a “completely anonymous experience”.

One downside: you have to manually record your daily basal body temperature (BBT) into the app.
Choose Daysy if you want an almost entirely error-free app. Daysy determines your fertility with a remarkable 99.4% accuracy. And, it automatically syncs with your smartphone app to give fertility statistics and reports. Not thrilled by the idea of measuring your BBT right when you wake up before you can even go to the bathroom? We recommend Ava, a bracelet that you wear during your sleep, allowing it to collect data overnight.

Ava is only for those looking to get pregnant and track their pregnancy progress. Ava is not for someone looking for a contraceptive device.

But don’t just take our word for it! Read on to get into the nitty-gritty of Natural Cycles, Daysy, and Ava. 


How effective is fertility tracking?  


In the wave of saving money and rapid results, self-tracking fertility apps are on the rise. Maybe you’ve hit a roadblock in your pregnancy journey and are struggling to conceive, or maybe you know it’s just not yet your time to have a child, but don’t want to use hormonal birth control. Whatever your motives are, there is a fertility tracking option for you. 


So, what is fertility tracking? Simply put, it is knowing when your fertile window is, and even more specifically, when you’re ovulating and could get pregnant. Fertility tracking apps help women predict when that fertile window is, and a recent study found that “the efficacy of a contraceptive mobile application is higher than usually reported for traditional fertility awareness-based methods and suggested that the application may contribute to reducing the unmet contraceptive planning needs for women”.


Fertility tracking apps (FTA) utilize three different accurate methods


  1. Daily oral basal body temperature to identify ovulation
  2. Cervical fluid consistency
  3. Urinary LH levels

The science behind fertility tracking apps is evolving and is not meant to be in place of a regular doctor visit, but instead allow for at-home, enhanced knowledge of your cycle and fertility. 


It seems rather empowering as a female to know when you can and can’t get pregnant, doesn’t it? Whether that information is used to avoid contraception or to help a woman get pregnant after many attempts lacking fertility knowledge, simply knowing more about your own cycle and body is a great tool.


Other benefits of hormone-free fertility tracking include: 


  • Enhanced knowledge of your cycle
  • A natural way to track your cycle
  • Side-effect free
  • Low-cost
  • Real-time knowledge, at home


Which Fertility Tracking App is best: Natural Cycles, Daysy, or Ava? 


When you’re tracking your fertility, you want to make sure the app you’re using is giving you exactly what you and your partner want. The good news is that there are several different FTA options to choose from, including Natural Cycles, Daysy, and Ava. Beyond the cost and process, there are different features and utilities for each that offer women the ability to select options ranging from a bracelet to a thermometer to track fertility. Let’s dive in and compare the options to see which fertility tracking method is best for you! 

Best fertility tracking apps: Natural Cycles vs Daysy vs Ava

PriceAnnual: $89.99
Monthly: $9.99
$299$279 to $359
Device/HardwareThermometerThermometerFertility Bracelet
Efficacy98% with perfect use 93% with typical use99.40%90%
Cycle tracking and ability to identify fertile window
Tracking device stores your data
Tracking device automatically syncs to the app?
Fertility cycle report/statistics
PMS, pain and other menstrual
cycle tracking
Effective for irregular cycles
IOS/ Android compatible app
FSA/HSA Eligible
Pregnancy tracking
FDA Cleared
Geographic AvailabilityShips to countries all around the world EXCEPT: Mexico, Argentina, Columbia, South Africa, Saudi Arabia, the United Arab Emirates, and ChileUS, Europe, and CanadaUS

Each fertility tracking method has an app that correlates with the procedure to store data and allows you to look back on your cycles, making all of your data extremely easily accessible, right at your fingertips. Now let’s explore each tracker in a bit more detail. 


Review of Natural Cycles hormone-free birth control 


Source: Natural Cycles


Natural Cycles was the first FDA-approved app for determining a woman’s fertility window to help in birth control and pregnancy planning and are one of the leading apps working on a “completely anonymous experience”. Natural Cycle’s co-founder and co-chief executive, Raoul Scherwitzl, told Wall Street Journal that “the goal is to make it so no one—not even us at Natural Cycles—can identify the user”.



The idea for Natural Cycles was conceived when founders Elina and Raoul decided they were in need of an effective method of natural birth control. The two set out on a journey of analyzing Elina’s own temperature and devising an intuitive algorithm for fertile days. 


The two founders used Natural Cycles, successfully, for its dual uses: both as a preventative and a planner. Ever since its inception, Natural Cycles has been carrying out its mission to pioneer women’s health and empower women with the knowledge of their own personal health. 


How does Natural Cycles work? 


Source: Natural Cycles


Natural Cycles can be purchased on either a monthly or annual subscription basis. A basal thermometer comes for free with the annual subscription, but must be purchased separately with the monthly subscription (available at most pharmacies). 


Natural Cycles uses an algorithm based on a woman’s basal body temperature to determine fertility status. It’s a rather simple process, really. All you have to do is measure your temperature, input in the app, and allow the algorithm to calculate your fertility, and voila: fertility and cycle knowledge in the palm of your hands. 


Measuring basal body temperature (BBT) is used to help detect ovulation. The algorithm created by the two founders is regulated, certified, and “learns the pattern of your unique cycle to work out daily fertility status”. You don’t have to measure BBT every day, but getting into a routine will help to allow the app and algorithm to understand your cycle better. 


Furthermore, information about your menstrual cycle length (taking fluctuations and irregularities into consideration) can help forecast your fertility. Finally, although not required, the results of your optional luteinizing hormone (LH) test (LH levels spike immediately before you ovulate) can also help determine your fertility. An LH test is performed using a urine test strip, which may be purchased at your local drugstore or through the Natural Cycles app


The Natural Cycles app gives you a clear daily status of green (not fertile) or red (use protection), so it’s crystal clear as to how you need to proceed during intercourse (depending on what you want, that is). 


This color scheme is clearly for those trying to prevent pregnancy. If you’re trying to conceive, the rules of the road are a bit backward – red means go, green means no (no conception, that is. Nothing to do with how you spend your time, though…). 


Source: Natural Cycles


Is Natural Cycles FDA approved?


Yes! Natural Cycles was approved by the FDA as the first app-based birth control in 2018.  


Is Natural Cycles covered by insurance?


Natural Cycles is not currently covered by insurance but can be purchased with FSA or HSA. 


Getting started with Natural Cycles


To get started, you must download (and purchase) the app. Natural Cycles offer various plans, making it truly a long-term fertility partner:


  • NC Birth Control (preventing pregnancy)
  • NC Plan Pregnancy (finding fertile days)
  • NC Follow Pregnancy (monitoring pregnancy)

Temperature readings must be taken first thing in the morning when you’re still in bed before you can even use the bathroom. To use the app, you’ll need a basal thermometer (which can be purchased separately or in combination). Basal thermometers are more sensitive than regular fever thermometers, as they show two decimals (which is significant, by the way!). It’s recommended to forgo taking your temperature on days when you are feeling sick and assume your temperature has risen due to illness.


You’ll enter your current temperature into the app, where you can also add data about your cycle to track symptoms and learn more about your unique menstrual cycle. There’s space for you to document any PMS, pain, sex drive, or mood changes. You can use those symptoms and a graph feature to see patterns. 


Source: Natural Cycles


How much does Natural Cycles cost?


There are two subscription plans available for Natural Cycles app:


  • Annual: $89.99 (includes the thermometer)
  • Monthly: $9.99 (thermometer at an additional cost)


If you want to test Natural Cycles before paying for the service, you may try it out in a free demo mode by installing the app.


How accurate is Natural Cycles?


Natural Cycles claims to be 98% effective with perfect use and 93% effective with normal use. What’s the difference between normal and perfect? Great question – perfect means not having unprotected sex on any of the red days, normal means maybe accidentally slipping up once or twice. Because Natural Cycles if FDA approved, they are required to monitor this effectiveness rate on a regular basis, so we know this is legit.


Compared to birth control methods like hormonal birth control pills or IUDs, it is less effective, but it’s more effective than methods