< How it Works

Peak Day Rule

You can assume infertility at the end of the fourth consecutive day (6:00 pm) following your Peak Day.

The Peak Day is the last day you see or feel cervical fluid of wet, slippery, or egg-white quality. Important is a definite change to a lesser quality of your cervical fluid.
When using 'FAM / NFP,' Lily shows infertility at the beginning of day five to cover the time between 6:00 pm of day four and 12:00 am of day five. When using 'NFP (AG NFP),' Lily shows infertility at the beginning of day four to cover the time between 6:00 pm of day three and 12:00 am of day four.

Note: Concerning the Temperature Shift Rule and the Peak Day Rule, whichever comes last overrules the other one.

Note: Whenever, and as long as you experience cervical fluid of any kind, you have to consider yourself to be fertile.


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