Evaluation of the impact of intraobserver variability on endometrial dating and the diagnosis of luteal phase defects

To determine the magnitude of intraobserver variation in dating endometrial biopsies and its impact on clinical management.

Blinded histopathologic interpretation of endometrial biopsy specimens 1 year apart by five pathologists.

Large military tertiary care center.

Endometrial biopsy specimens from 51 patients undergoing evaluation for potential luteal phase defects.

None.

Calculation of the magnitude of the individual and overall intraobserver variation in endometrial dating for the five pathologists and estimation of its potential impact on clinical management.

The intraobserver variation was 0.69 +/- 0.05 days (means +/- SE). There was no significant difference in the magnitude of the variation for 1-day or 2-day dating ranges. The theoretical probability of altering clinical management by having the same pathologist redate a given specimen ranged from 15% to 28%.

Histologic dating of endometrial biopsies is subject to a small but highly clinically significant intraobserver variability that may have a major impact on clinical management.