Basal Body Temperature as a Method of Ovulation Detection: Comparison with Ultrasonographical Findings

Abstract

In 47 cycles with hormonal evidence of ovulation, the detection and timing of ovulation by basal body temperature (BBT) and by ultrasonographical observation are compared. The ovulation detection rate by ultrasonographical method proves to be considerably higher than by BBT criteria. The timing of the day of ovulation is evaluated, assuming that the ultrasonographical event of follicle disappearance represents ovulation. BBT criteria nadir, coverline and the eye-balling method show a very poor frequency distribution. The result of the FDHP method is a nearly symmetrical distribution, however, with a considerable range. We conclude that ovulation detection and timing by BBT are not reliable.

Ultrasound Increases the Prognostic Value of the Postcoital Test

“…Wetzels el al. [14] described the inaccuracy of the BBT in timing the exact moment of ovu lation compared with ultrasound. The results of the present investigation indicate that, if in infertility clinics adequate ultrasound equip ment is available, there is no need for the BBT anymore in the standard fertility inves tigation.…”

“Stepchild”: Observation of the Menstrual Cycle

“…Das hat natürlich zu überraschenden Schwangerschaften geführt. Es liegt eine Variationsbreite der möglichen Tage der Ovulation zum ¹Nadirª von insgesamt sechs bis zehn Tagen vor, darunter bis zu sechs Tagen nach dem ¹Nadirª [15,27,29].…”