A new method to detect significant basal body temperature changes during a woman's menstrual cycle

Area of Science:

• Reproductive Health
• Biotechnology
• Medical Informatics

Background:

• Natural family planning (NFP) relies on identifying fertile windows.
• Basal body temperature (BBT) tracking is a key NFP method.
• Accurate identification of the BBT shift day is crucial for NFP effectiveness.

Purpose of the Study:

• To compare a computer-based Trigg's tracking system (TTS) for identifying the basal body temperature (BBT) shift day with the established Sensiplan symptothermal method.
• To evaluate the accuracy and timeliness of TTS in determining the BBT shift day.

Main Methods:

• A computer program was developed to analyze daily BBT readings from 364 menstrual cycles of 51 women (aged 24-35) from the German NFP database.
• The program identified the TTS transition day (BBT shift day).
• This TTS-identified day was compared against the BBT shift day determined by the Sensiplan method.

Main Results:

• Total agreement between the TTS and Sensiplan methods was observed in 81% of cycles (294/364).
• 18% of cycles (67/364) showed a difference of ±1 day.
• The median differences between the TTS transition day and Sensiplan shift day were not statistically significant (p=0.07205).

Conclusions:

• The Trigg's tracking system algorithm demonstrates high agreement with the Sensiplan method for identifying the BBT shift day.
• A key advantage is the potential to identify the BBT shift day on the same day it occurs, rather than retrospectively.
• The algorithm allows estimation of the probability of a temperature transition, enhancing fertility awareness.