Utility of endometrial multi-vessel blood flow ultrasound parameters in predicting pregnancy outcomes

To evaluate the endometrium using multi-vessel blood flow ultrasound parameters and explore their potential utility in predicting pregnancy outcomes.

A total of 205 women were included in the study. Transvaginal three-dimensional ultrasound was used to evaluate luteal phase endometrial thickness, volume, and three-dimensional power Doppler blood flow parameters of the endometrium (vascularization index [VI], flow index [FI], and vascularization flow index [VFI]), as well as the endometrial microvascular vascularization index (VI_MV). Additionally, the systolic/diastolic ratio (S/D), pulsatility index (PI), and resistance index (RI) of the bilateral uterine arteries were measured. Based on pregnant outcomes, participants were divided into two groups: a clinical pregnancy group and a non-pregnancy group, and ultrasound parameters were compared between these groups.

Women in the clinical pregnancy group showed significantly higher levels of endometrial FI, VI, VFI, and VI_MV compared to those in the non-pregnancy group (p<0.05). Conversely, the S/D, PI, RI, and mean levels of bilateral uterine arteries were significantly lower in the pregnancy group than in the non-pregnancy group (p<0.05). VI_MV (area under the ROC curve [AUC] 0.869; sensitivity 92.2 %, specificity 68.8 %), VFI (AUC 0.761; sensitivity 96.9 %, specificity 53.9 %), FI (AUC 0.707; sensitivity 79.7 %, specificity 46.1 %), and VI (AUC 0.637; sensitivity 90.6 %, specificity 51.8 %) all showed a significant strong positive correlation with endometrial thickness (r>0, p<0.05), indicating their role in predicting pregnancy.

Multi-vessel blood flow parameters reflect the endometrial blood perfusion state and are closely associated with the likelihood of achieving a successful pregnancy.