Bilateral notching of uterine arteries at 12--14 weeks of gestation for prediction of hypertensive disorders of pregnancy.

OBJECTIVE

To assess the value of transvaginal uterine artery Doppler ultrasound at 12--14 weeks of gestation in predicting hypertensive disorders of pregnancy in high-risk women.

METHODS

One hundred and twenty high-risk women were evaluated prospectively by Doppler ultrasound of uterine and umbilical arteries at 12--14 weeks of gestation. The presence of bilateral notches, resistance and pulsatility index (PI), mean and maximum flow velocities of uterine arteries, and resistance and PI of umbilical arteries were investigated. Those with bilateral notching were randomized to acetylsalicylic acid (n=43) or placebo groups (n=43) and were followed up twice during pregnancy with the same ultrasound measurements. The women without bilateral notches (n=29) served as controls. In this study, we compared 43 women in the placebo group to 29 controls without bilateral notches. The outcome measures were pregnancy-induced hypertension, pre-eclampsia and intrauterine growth restriction.

RESULTS

The sensitivity of bilateral notching in predicting hypertensive disorders of pregnancy decreased with advancing pregnancy from 91 to 35%, and the specificity and the positive predictive values increased from 41 to 94% and from 7 to 70%, respectively. The negative predictive values ranged from 86 to 97%.

CONCLUSION

Bilateral notching of uterine arteries at 12--14 weeks is a useful tool in predicting the development of hypertensive disorders in high-risk pregnancies. It is also a suitable test for surveillance of high-risk pregnancies.