An objective method for detecting the shift in basal body temperature in women

Area of Science:

• Reproductive Endocrinology
• Biostatistics
• Natural Family Planning

Background:

• Basal body temperature (BBT) shifts indicate ovulation and the start of the infertile period.
• Accurate detection of BBT shifts is crucial for natural family planning (NFP) programs.
• Physiological variations can complicate reliable BBT shift detection.

Purpose of the Study:

• To adapt and apply the cumulative sum (CUSUM) test for reliable BBT shift detection.
• To minimize user uncertainty in identifying the fertile and infertile phases of the menstrual cycle.
• To validate the CUSUM test's efficacy in natural family planning contexts.

Main Methods:

• The cumulative sum (CUSUM) statistical test was adapted for BBT data analysis.
• The adapted CUSUM test was applied to 137 BBT charts from 21 women.
• Data was collected from women utilizing natural family planning methods.

Main Results:

• The CUSUM test successfully detected BBT shifts in all analyzed cases.
• Detected shifts occurred at gynecologically appropriate times within the menstrual cycle.
• The method demonstrated high reliability and reduced user uncertainty.

Conclusions:

• The adapted CUSUM test is a reliable tool for detecting ovulation-related BBT shifts.
• This method enhances the accuracy of natural family planning by clearly defining the infertile period.
• The CUSUM test offers a statistically sound approach to fertility awareness.