This is how the ovolution app analyses data according to NFP rules
The ovolution app analyses fertile and infertile phases based on the symptothermal method of Natural Family Planning (NFP). You record your basal body temperature daily, as well as cervical mucus or changes in the cervix – the app evaluates both according to the Sensiplan® rules.
Temperature recording
The temperature is entered to two decimal places and rounded to the nearest 0.05 or 0.00. A good basal thermometer is essential, as changes in the tenths of a degree range are crucial.
Fertile period at the start of the cycle
5-day rule
Beginners should treat the first five days of the cycle as infertile, provided that a temperature peak was detected in the previous month. Exceptions apply if cervical mucus or changes in the cervix occur earlier – in which case the fertile window begins correspondingly earlier.
Minus-8 rule
After analysing 12 cycles, experienced users can take the first higher reading from all cycles analysed so far and subtract eight days. This gives the end of the infertile days at the start of the cycle – a personalised and more reliable method than the standard 5-day rule.
Determining ovulation
Ovulation is indicated by three consecutive readings, all of which are higher than the previous six measurements. The third reading must be at least 0.2 degrees higher than the baseline temperature.
If these criteria are not fully met, the app applies the exceptions defined in Sensiplan®.
Double check after ovulation
The double check after ovulation means that the later bodily sign determines the start of the infertile period. So, if the temperature has already risen but the cervical mucus still appears fertile, the infertile period does not begin until the mucus sign has also concluded – and vice versa.
What you’ll see in the app
- The current cycle day and the current phase (fertile / possibly fertile / infertile)
- The temperature trend as a graph
- The analysis according to NFP rules with explanations
- The length of your luteal phase (progesterone phase)
- Notes on spotting or any unusual symptoms
Why analyse according to NFP rules?
Calendar-based apps only estimate fertile days – based on average values. The ovolution app monitors your actual bodily signs and analyses them individually. This makes a big difference, especially with irregular cycles.