Should bilateral uterine artery notching be used in the risk assessment for preeclampsia, small-for-gestational-age, and gestational hypertension?

Abstract

Objective: The purpose of this study was to determine the value of bilateral uterine artery notching in the second trimester in the risk assessment for preeclampsia, gestational hypertension, and small-for-gestational-age (SGA) without preeclampsia.

Methods: This prospective cohort study included 4190 singleton pregnancies that underwent ultrasound examination between 23 and 25 weeks' gestation. The 95th percentiles of the mean pulsatility index (PI) and resistive index (RI) of both uterine arteries were calculated. Multivariable logistic regression analyses were performed to determine if bilateral uterine artery notching is an independent explanatory variable for the occurrence of preeclampsia, early-onset preeclampsia (<or=34 weeks), late-onset preeclampsia (>34 weeks), gestational hypertension, and delivery of an SGA neonate without preeclampsia, while controlling for confounding factors.

Results: (1) The prevalence of preeclampsia, early-onset preeclampsia, late-onset preeclampsia, SGA, and gestational hypertension were 3.4%, 0.5%, 2.9%, 10%, and 7.9%, respectively; (2) 7.2% of the study population had bilateral uterine artery notching; and (3) bilateral uterine artery notching was an independent explanatory variable for the development of preeclampsia (odds ratio [OR], 2.1; 95% confidence interval [CI],1.28-3.36), early-onset preeclampsia (OR, 4.47; 95% CI, 1.50-13.35), and gestational hypertension (OR, 1.50; 95% CI, 1.02-2.26), but not for late-onset preeclampsia or SGA.

Conclusions: Bilateral uterine notching between 23 and 25 weeks' gestation is an independent risk factor for the development of early-onset preeclampsia and gestational hypertension. Thus, bilateral uterine artery notching should be considered in the assessment of risk for the development of these pregnancy complications.

Figure 1. Comparison of areas under the curve (AUC) of Doppler parameters in the prediction of preeclampsia

The presence of a bilateral uterine artery notching and/or a mean uterine artery PI>95% percentile had the highest auc (0.619) for the prediction of preeclampsia. However, the auc of the combination of these Doppler parameters was significantly higher than that of bilateral notching alone (auc: 0.578; p=0.02) but not significantly higher than the combination of bilateral uterine artery notching and/or a mean uterine artery RI>95% percentile (auc: 0.612; p=0.53), or a mean uterine artery PI or RI >95% (auc: 0.577, p=0.05 and auc: 0.570, p=0.05; respectively).

Figure 2. Comparison of areas under the curve (auc) of Doppler parameters in the prediction of early-onset preeclampsia

The presence of bilateral uterine artery notching and/or a mean uterine artery PI or RI>95% percentile had the highest auc (0.821) for the prediction of early-onset preeclampsia. However, the auc of the combination of these Doppler parameters was not significantly higher than that of bilateral notching alone (AUC: 0.73; p=0.07) or that of a mean uterine artery PI or RI >95% (auc: 0.767, p=0.65 for both comparisons).