Basal body temperature: unreliable method of ovulation detection

Area of Science:

• Gynecology
• Reproductive Endocrinology
• Medical Diagnostics

Background:

• Basal body temperature (BBT) charting is a commonly used method for tracking ovulation.
• Accurate ovulation timing is crucial for fertility awareness and reproductive health assessments.
• Previous studies have suggested variability in BBT charting accuracy.

Purpose of the Study:

• To evaluate the accuracy of Basal Body Temperature (BBT) charting in determining ovulation timing.
• To compare BBT chart interpretations with endocrine profiles and luteinizing hormone (LH) peaks.
• To assess the reliability of BBT charting for clinical and research applications.

Main Methods:

• Retrospective analysis of BBT charts from 98 women.
• Evaluation of charts by six experienced physicians to determine ovulation timing.
• Comparison of physician-estimated ovulation timing with endocrine profiles and LH surge detection.
• Identification of ovulatory and adequate luteal phase cycles based on endocrine data.

Main Results:

• Physician consensus on BBT charts accurately predicted ovulation timing within +/- 1 day of the LH peak in only 22.1% of ovulatory cycles.
• An additional 22.1% of cycles were incorrectly identified as monophasic by physicians.
• Significant discrepancies were observed between BBT interpretations and objective endocrine measures.

Conclusions:

• Basal body temperature charting demonstrates low accuracy in determining ovulation timing.
• Clinical and research reliance on BBT for ovulation assessment is not recommended due to high variability.
• Extreme caution is advised when interpreting BBT charts for menstrual cycle dynamics and ovulation.