Reproducibility of first trimester three-dimensional placental measurements in the evaluation of early placental insufficiency.

OBJECTIVE

To evaluate the reproducibility of first-trimester, three-dimensional placental volume and vasculature evaluation by ultrasound in correlation with uterine artery Doppler flow studies.

METHOD

We performed a prospective study of a cohort of pregnant women undergoing first-trimester ultrasound examination. Uterine artery Doppler and 3-D power Doppler angiography was performed. Placental volume, vascularization index (VI), flow index (FI), and vascularization flow index (VFI) were calculated three times by two independent observers using the virtual organ computer-aided analysis (VOCAL) software. Intra- and interobserver reproducibility was evaluated by Spearman's correlation test. All parameters between women with low (< 1.5 multiple of median) (MoM) and high (> 1.5 MoM) uterine artery Pourcelot index (PI) were compared by the Mann-Whitney test.

RESULTS

A total of 35 women between 11 and 14 weeks' gestation were recruited, including 26 who underwent uterine artery Doppler and six with elevated uterine artery PI. We found excellent intra- and interobserver reproducibility (R2 > 0.85) for all parameters. Women with elevated uterine artery PI had smaller placental volume, VI, FI, and VFI (P < 0.05).

CONCLUSION

3-D placental volume and vasculature evaluations during the first trimester are reproducible measures that inversely correlate with uterine artery PI.