The symptothermal method is based on the evaluation of two or more body signals to determine the fertile days in the cycle. It is important to document your body signals on a daily basis and also to get to know your body and its signals very well.
The symptothermal method is a non-invasive method that does not affect the hormonal balance. All you need to use the method is a basal thermometer that measures to two decimal places. The symptothermal method is used to determine the fertile days of the female menstrual cycle. Changes in basal body temperature and cervical mucus are measured. The symptothermal method has a proven Pearl Index of 0.4 in perfect use (without application errors) and 1.8 in typical use.
This means that if 100 women* use the symptothermal method for one year, 0.4 to 1.8 unwanted pregnancies occur.
*Source: Leitlinien der Deutschen Gesellschaft für Gynäkologie und Geburtshilfe Juli 2004, pro familia