Role of three-dimensional ultrasonographic measurement of endometrium volume as a predictor of pregnancy outcome in an IVF-ET program: a preliminary study

Objective: To evaluate the role of three-dimensional (3D) ultrasonographic measurement of the endometrium in predicting pregnancy in an IVF-ET program. Design: Prospective study. Setting: Center for assisted reproductive techniques. Patient(s): 65 women undergoing controlled ovarian hyperstimulation for IVF. Intervention(s): Ultrasonographic examination on the day of hCG administration. Main Outcome Measure(s): Endometrial volume, endometrial thickness, and pregnancy rate. Result(s): The mean (±SD) endometrium volume (4.16 ± 1.97 mL), endometrium thickness (11 ± 2 mm), and estradiol level (1686.82 ± 1057.10 pg/mL) in 21 pregnant women on the day of hCG administration did not differ statistically differ from the respective values in 44 nonpregnant women (4.53 ± 1.79 mL; 11 ± 2 mm, 1883.56 ± 1147.21 pg/mL). Receiver-operating characteristic curves showed that the area under curve (AUC) was 0.57 for endometrial volume and 0.48 for endometrial thickness. Using a cut-off value of 2.5 mL for endometrial volume to predict pregnancy, results of the Fisher exact test were statistically significant. No significant cut-off value was found for endometrial thickness. Conclusion(s): Endometrial volume and thickness on the day of hCG administration did not predict occurrence of pregnancy. A minimum volume of 2.5 mL appeared to favor pregnancy. The predictive value of 3D ultrasonographic measurement of endometrial volume and thickness was better than that of 2D measurement.