Detection of benign endometrial masses by endometrial stripe measurement in premenopausal women

Our objective was to estimate whether a transvaginal endometrial stripe of less than 5 mm in premenopausal women would exclude endometrial polyps and intracavitary leiomyomata, thereby eliminating the need for sonohysterography.

Data from 206 consecutive sonohysterograms performed in premenopausal women with abnormal uterine bleeding between August 1998 and October 2001 were collected retrospectively. Endometrial stripe measurements were obtained in the sagittal plane before sonohysterography. Baseline endometrial stripe images were reviewed by one of the authors, who was blinded to sonohysterography and pathology results, to evaluate for gross endometrial abnormalities on transvaginal ultrasonography.

Endometrial stripe measurements were obtained before sonohysterography in 200 of the 206 consecutive exams in premenopausal subjects. Of the 80 subjects with an endometrial stripe measurement less than 5 mm, 11 had endometrial polyps and 5 had submucosal fibroids on sonohysterography. With an endometrial stripe thickness of less than 5 mm, the sensitivity was 74% (95% confidence interval 62-84), the specificity was 46% (95% confidence interval 38-54), the positive predictive value was 37%, and the negative predictive value was 80%. The detection of pathology was not improved by excluding cases with an abnormal-appearing endometrial stripe on the baseline transvaginal images. The use of other endometrial stripe cutoff values did not improve the diagnostic accuracy.

Using an endometrial stripe cutoff of 5 mm in premenopausal women would miss significant intracavitary pathology. The sonographic evaluation of abnormal uterine bleeding in premenopausal women should include sonohysterography or equivalently accurate testing regardless of endometrial stripe thickness.