Reproducibility of transvaginal three-dimensional endometrial volume measurements with virtual organ computer-aided analysis (VOCAL) during ovarian stimulation.

Objective: To calculate inter- and intraobserver reliabilities for three-dimensional endometrial volume measurements during in vitro fertilization using virtual organ computer-aided analysis (VOCAL).

Patients And Methods: Three-dimensional ultrasound measurements of the endometrium using VOCAL software were performed on the day of oocyte retrieval in each of 79 consecutive patients undergoing in vitro fertilization or intracytoplasmic sperm injection. Endometrial volume was calculated every 15 degrees and every 30 degrees by two different observers in order to determine the reproducibility of the technique.

Results: Intraobserver reliability for the 15 degrees measurements was 0.97 for both observers; for the 30 degrees measurements, it was 0.93 for one observer and 0.96 for the other. Interobserver reliability was 0.80 for the endometrial volumes calculated every 15 degrees and 0.83 for the volumes calculated every 30 degrees. The intra- and interobserver measurement agreement showed good reproducibility. However, the volumes calculated every 15 degrees were more accurate because the means of differences were close to zero.

Conclusion: VOCAL provides a reproducible method for the estimation of the endometrial volume.