Reproducibility of transvaginal ultrasonographic measurements of endometrial thickness in patients with postmenopausal bleeding.

The aim of the study was to establish the reproducibility of transvaginal sonographic measurements of endometrial thickness in patients with postmenopausal bleeding (PMB). In a prospective blind study, two examiners measured the endometrial thickness in 48 patients presenting with PMB by transvaginal sonography on two separate occasions, 30 min apart. The analysis of variance performed at each endometrial thickness measured by the two examiners revealed no statistical difference. However, it was shown that the most accurate measurements are up to the level of 4 mm (mean deviation of 0.1 +/- 0.2 mm, range 0.7). Once the endometrial thickness reaches 5-6 mm the mean deviation becomes 0.3 +/- 1.2 mm with a range of variation of 4 mm. In conclusion, measurements of endometrial thickness in patients presenting with PMB can be repeated quite accurately up to a level of 4 mm thickness.