Fertilty Monitoring Apps – Are they Reliable?

Dozens of apps on the market currently claim to be an alternative to traditional contraceptive methods such as the pill. These apps promise women freedom from the possible hormonal side-effects associated with the pill which can range from decreased libido to depression. But given that reports about the reliability of these methods have been so conflicting, it’s hard to know what to think.

On the one hand organisations like the Karolinska Institute in Sweden recently published a study stating that apps were as effective as the pill at preventing pregnancies. The researchers examined how effective apps were among 4,054 Swedish women aged 20-35, by establishing how many of them became pregnant within a year. On the other hand, the German Association of Endocrinologists also released a statement discouraging women from using apps to prevent pregnancy. They warned of the potential for errors inherent in a system that requires lay people to interpret delicate data. The association also pointed out that many apps do not account for the large fluctuations possible in an individual woman’s cycle.

I spoke to a popular German blogger at wearetheladies.de who has written extensively about what it’s like to use contraceptive apps. Going by the pen name “Maggie” she reports on the three years she spent using non-hormonal technology such as fertility monitors and apps.

Andrews:  Many scientists advise against apps as a contraceptive. Why did you consider them reliable anyway?

Maggie: The problem with apps as contraception lies in choosing the right one. Most of them are based on the calendar method, which is very uncertain. So it is highly important to find an app that supports the symptothermal method (temperature measurement + cervical fluid monitoring) which makes determinations based on these two metrics. You should also familiarise yourself with the app beforehand and learn about the rules and terminology. Only then will you be able to use the correct app as a form of contraception. Also, the interpretation of the results should always be done attentively and it should be double checked – never just blindly rely on the technology.

Andrews: How would you describe your transition from using fertility monitors to working with apps?

Maggie: The transition was seamless for me because, thanks to the fertility monitors I had previously used, I already had 18 months worth of experience with the symptothermal method, so I already felt very comfortable with it. I chose the myNFP app, which in my opinion is the best on the market when it comes to natural contraception. So I didn’t have any problems. On the contrary: I was excited about the many additional features the app had in contrast to the rudimentary fertility monitor – since then much better models (that I would recommend) have become available.

Andrews: Do women need to know their cycles very well to be able to use apps effectively?

Maggie: No. Because the “right” apps are not based on the calendar method you do not need to know your cycle particularly well. The appropriate apps do not predict ovulation, instead they try to figure out when it is happening in each cycle, using bodily symptoms. So fluctuations are no problem – by the way, they are normal among most women. The 28 day cycle is a total myth and an invention of the the pharmaceutical industry.
Andrews: Who would you recommend apps to and who would you discourage from using them?

Maggie: Generally I would recommend that women who are just starting out with natural contraception begin with a fertility monitor. It is a much smoother introduction and offers you much more certainty. But at the same time, you should still find out about the device before using it; if only to know how to deal with possible problems.

If you are unsure and don’t want to invest too much money then you can also start with an app right away. But then you need to really master how to read off the data and correctly enter temperature information into the system. Some women feel overwhelmed at the prospect of reading an analogue thermometer, for instance – I would definitely recommend a fertility monitor over an app for this step. When I started out I only felt comfortable using natural contraception in tandem with a fertility monitor – I don’t think there’s any shame in that. At the end of the day it is a new experience that is filled with uncertainty. But you’ll be able to figure things out in just a few cycles, I promise.

Andrews: Do you think it will ever be possible to develop an app that is as reliable as a computer?

Maggie: Yes and no. I think apps that are operated manually by the user will always give rise to a certain number of errors, no matter how well they are programmed. But we are starting to see more apps on the market that connect to a bluetooth thermometer, such as WINK/KINDARA from the U.S. or OVY in Europe. The thermometer incorporates the information automatically so that the problems associated with approximation and data capture fall away. To me this is an ideal solution, something between apps and computers, although I have not tested one yet.
But I would like to say, on behalf of apps: if you choose the right one, thoroughly inform yourself about the method beforehand, follow your cycle closely and double check the results, then you can safely use apps as a contraceptive.

Salusdigital acknowledges that all of the methods mentioned above cannot guarantee 100 percent reliability, therefore we do not accept any liability for any pregnancies that may result during their use.


T L Andrews


TL Andrews is a multi-media journalist based in Berlin. He produces features for radio, television and print outlets with a focus on German and European issues.

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