Role of First- and Second-Trimester Uterine Artery Doppler in Predicting Adverse Pregnancy Outcomes: A Review of Literature

Literature review

Abstract

Background: Uterine artery Doppler velocimetry (UADV) is a non-invasive tool for assessing uteroplacental blood flow and identifying pregnancies at risk for pre-eclampsia (PE), fetal growth restriction (FGR), and small for gestational age (SGA). While abnormal indices such as elevated pulsatility index (PI), resistance index (RI), and persistent bilateral notching have been consistently associated with placental insufficiency, the clinical value of UADV depends on the timing of assessment, threshold definitions, and integration with other screening modalities.

Methods: This review synthesises evidence from eight high-quality studies published between 1998 and 2023, encompassing large multicentre prospective cohorts, randomised controlled trials, and meta-analyses. The studies varied in gestational age at Doppler assessment (first trimester, mid-trimester, and serial approaches), measurement technique (transabdominal or transvaginal), and criteria for abnormality (centile-based thresholds or fixed cut-offs). Outcomes assessed included PE, FGR, SGA, and composite maternal-fetal morbidity.

Results: Mid-trimester UADV demonstrated the strongest standalone predictive value, with detection rates of up to 69–93% for severe early-onset PE and FGR and ~60% for early PE/IUGR in a large randomised trial ^1,2. First-trimester Doppler alone had modest sensitivity for overall PE and SGA but was more predictive of severe phenotypes, with Martin et al. (2001) reporting 60% detection for PE requiring delivery before 32 weeks. Incorporation into multimodal algorithms, as in the ASPRE trial, achieved 76.7% detection of preterm PE at a 10% false-positive rate and, when combined with aspirin prophylaxis, reduced preterm PE incidence by over 60% ³. Smaller cohort studies and a large meta-analysis reinforced the predictive role of UADV across gestation, with the highest effect sizes in mid-to-late pregnancy.

Conclusion: The evidence consistently supports UADV as a valuable screening tool, particularly for early-onset, severe placental disease. Mid-trimester measurement offers the best standalone performance, while first-trimester assessment gains maximum utility within integrated risk models that link detection to effective interventions. Limitations include heterogeneity in technique, population differences, and the limited impact of Doppler-only strategies on outcomes without accompanying treatment pathways. This synthesis underpins the rationale for including UADV in structured screening programmes and informs the methodological approach of the present thesis.