Predictive Value of Uterine Artery Pulsatility Index in Placental Insufficiency Across Gestational Stages in a Single...

To assess the predictive significance of the uterine artery pulsatility index (UTPI) for placental insufficiency (PI) during different stages of pregnancy within the same population, identify the optimal detection window, and elucidate its dynamic variation patterns.

Standardized UTPI measurements were obtained at 6 gestational stages (11-13⁺⁶ w to 32-36⁺⁶ w). PI, including preeclampsia (PE) and fetal growth restriction (FGR), was the primary outcome. Longitudinal UTPI trends were analyzed using generalized linear mixed models, and gestational stage-specific predictive performance was assessed using receiver operating characteristic (ROC) analysis.

A total of 129 high-risk singleton pregnancies were included (114 normal, 15 with PI). UTPI decreased with advancing gestation in both groups (β = -0.195, p < .001) but remained consistently higher in the PI group. The predictive performance varied by gestational stage, peaking at 24-27⁺⁶ w (AUC 0.79, 95% confidence interval (CI) 0.64-0.92; sensitivity 80.0%, 95% CI 50.0-100.0; specificity 74.6%, 95% CI 69.0-96.0). At 28-31⁺⁶ weeks, the UTPI showed comparable discriminative ability (AUC 0.78, 95% CI 0.62-0.92), with moderate sensitivity (66.7%, 95% CI 47.0-100.0) and high specificity (83.3%, 95% CI 45.0-97.0).

The UTPI has a gestational stage-dependent predictive value for PI, with optimal discrimination at 24-27⁺⁶ weeks and a subsequent risk-confirmation phase at 28-31⁺⁶ weeks. Both groups exhibited similar UTPI decline patterns, indicating the presence of hemodynamic compensation in PI patients. These findings support the use of a phased UTPI monitoring strategy in high-risk pregnancies.