Methods that require observation of one or more of the three primary fertility signs (basal body temperature, cervical mucus, and cervical position) are known as symptoms-based methods.
Metoder, der kræver observering af et eller flere af de tre primære frugtbarhedstegn (basal kropstemperatur, ægløsningsslim ("cervikalsekret") og livmoderhalsens placering) kendes som symptombaserede metoder.