Digital Cycle Apps
How reliable are cycle apps really? We provide a scientific assessment of app types, methods and certifications.
Cycle apps are used by many women, to monitor their own cycle, when trying to conceive or for contraception. However, our scientific analyses show that the quality and reliability of these applications vary considerably and are often difficult for users to assess.
As part of our CONtraCEPT project, we are investigating
- how cycle apps and digital measurement systems work,
- how user-friendly they are and
- how reliably they can determine the fertile window and the infertile days.
Understanding cycle apps
Cycle apps record and analyse various pieces of information about the menstrual cycle. They divide the menstrual cycle into fertile and infertile days. In this way they define a fertile window, that is, a period during which a pregnancy can occur. This information is reliable in some apps but not sufficiently reliable in others. For every woman, the fertile window covers only a few days of the cycle. This period, and therefore the day of ovulation, can vary from month to month. As a result, it is not possible to reliably predict the timing of ovulation and the fertile window.
Important to note
Ovulation itself cannot be measured directly and varies in timing. What can be determined is the fertile window.
Different types of app
Digital cycle apps can be broadly divided into three groups.
1
Prediction apps
Calendar-based prediction
These apps calculate fertile days based on past cycle data and use average values. Because the cycle can change, such predictions are unreliable.
2
NFP apps
Natural family planning, symptothermal
Some of these apps are based on scientifically sound methods and use current bodily signs such as basal body temperature and cervical mucus. They can narrow down the fertile window in the current cycle more accurately. Using them requires knowledge and active involvement.
3
Apps with measurement systems
e.g. wearables
These use additional data, for example from sensors or hormone measurements. Many of these technologies have not yet been sufficiently studied scientifically and sometimes deliver unreliable results.
Opportunities and limits
Cycle apps can help you develop a better understanding of your own cycle and promote health awareness.
At the same time, many applications have so far not been sufficiently tested scientifically. In particular, the precise determination of the fertile and infertile days is often uncertain, because the cycle can vary from person to person.
Assessing certifications
Many cycle apps advertise certifications such as the CE mark, TÜV seal or FDA approval. However, these do not provide reliable information about how effective an app actually is at determining the fertile window and the infertile days. The assessment is often based on manufacturers’ own claims and usually not on independent scientific studies. For users, the quality of cycle apps is therefore often difficult to judge. This is exactly where our research project comes in.
JOIN THE RESEARCH
Help us test cycle apps independently
We investigate how reliably apps determine the fertile window and what certifications such as CE or FDA really mean. Write to us if you would like to share your experiences with apps or take part in our research.
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