Use of uterine artery Doppler ultrasonography to predict pre-eclampsia and intrauterine growth restriction: a systematic review and bivariable meta-analysis.
BACKGROUND
Alterations in waveforms in the uterine artery are associated with the development of pre-eclampsia and intrauterine growth restriction. We investigated the predictive accuracy of all uterine artery Doppler indices for both conditions in the first and second trimesters.


METHODS
We identified relevant studies through searches of MEDLINE, EMBASE, the Cochrane Library and Medion databases (all records to April 2006) and by checking bibliographies of identified studies and consulting with experts. Four of us independently selected studies, extracted data and assessed study validity. We performed a bivariable meta-analysis of sensitivity and specificity and calculated likelihood ratios.


RESULTS
We identified 74 studies of pre-eclampsia (total 79,547 patients) and 61 studies of intrauterine growth restriction (total 41 131 patients). Uterine artery Doppler ultrasonography provided a more accurate prediction when performed in the second trimester than in the first-trimester. Most Doppler indices had poor predictive characteristics, but this varied with patient risk and outcome severity. An increased pulsatility index with notching was the best predictor of pre-eclampsia (positive likelihood ratio 21.0 among high-risk patients and 7.5 among low-risk patients). It was also the best predictor of overall (positive likelihood ratio 9.1) and severe (positive likelihood ratio 14.6) intrauterine growth restriction among low-risk patients.


CONCLUSIONS
Abnormal uterine artery waveforms are a better predictor of pre-eclampsia than of intrauterine growth restriction. A pulsatility index, alone or combined with notching, is the most predictive Doppler index. These indices should be used in clinical practice. Future research should also concentrate on combining uterine artery Doppler ultrasonography with other tests.
Cnossen
Jeltsje S
JS
Department of General Practice, Academic Medical Center, Amsterdam, The Netherlands. j.s.cnossen@amc.uva.nl
Morris
Rachel K
RK
ter Riet
Gerben
G
Mol
Ben W J
BW
van der Post
Joris A M
JA
Coomarasamy
Arri
A
Zwinderman
Aeilko H
AH
Robson
Stephen C
SC
Bindels
Patrick J E
PJ
Kleijnen
Jos
J
Khan
Khalid S
KS
D000328:Adult; D001158:Arteries / Q000000981:diagnostic imaging*; D016001:Confidence Intervals; D005260:Female; D005317:Fetal Growth Retardation / Q000175:diagnosis* / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D021041:Placental Circulation / Q000502:physiology; D011225:Pre-Eclampsia / Q000175:diagnosis* / Q000453:epidemiology; D011237:Predictive Value of Tests; D011247:Pregnancy; D011256:Pregnancy Outcome; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D011673:Pulsatile Flow; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D018608:Ultrasonography, Doppler; D016216:Ultrasonography, Prenatal; D014599:Uterus / Q000098:blood supply* / Q000000981:diagnostic imaging