The use of uterine artery doppler indices for prediction of pre-eclampsia in Port-Harcourt, Nigeria.

Abstract

Pre-eclampsia (PrE), a clinical syndrome characterised by elevated blood pressure arising after 20 weeks of gestation, is a leading cause of maternal death worldwide. We evaluated the role of uterine artery Doppler (UtAD) in screening for PrE among unselected, pregnant women. This was a prospective cohort study of 170 healthy gravid women between 18 and 26 weeks of gestation recruited consecutively from the Antenatal Clinic of Braithwaite Memorial Specialist Hospital, Port-Harcourt, Nigeria, between July 2016 and June 2017. All had UtAD scans with an abnormal result defined as pulsatility index (PI), resistance index or systolic/diastolic (S/D) ratio >95th centile for gestational age or proto-diastolic notching. Outcome was obtained from antenatal records. Data were analysed using Statistical Package for Social Sciences, version 20 at statistical significance level of P < 0.05. The prevalence of PrE was 7.6%. There was significant association between an abnormal PI (χ2 = 16.29, P = 0.00), S/D ratio (χ2 = 8.55, P = 0.00) and the combined result (χ2 = 11.5, P = 0.007) with subsequent PrE. The highest sensitivity (53.8%) was obtained for the combined result with specificity, negative predictive value (NPV) and positive predictive value of 86.6%, 95.8% and 25%, respectively, area under the curve (AUC) of 0.71 (95% confidence interval [CI]: 0.534-0.871). A normal result had a very high NPV for all indices. The accuracy for the prediction of severe PrE was greater for all indices being highest for the combined result AUC of 0.830 (95% CI: 0.624-1.000; P = 0.01). Abnormal UtAD indices were associated with PrE and may be used in PrE screening.