Clinical implementation of the sFlt-1/PlGF ratio to identify preeclampsia and fetal growth restriction: A prospective cohort study.

OBJECTIVE: To analyze the usefulness of a clinical protocol for early detection of preeclampsia and/or fetal growth restriction (PE/FGR) using, in previously selected pregnancies, the measurement of the sFlt-1/PlGF ratio at 24-28 weeks of gestation.

STUDY DESIGN: Prospective observational cohort study carried out in a single tertiary hospital in Spain. 5601 consecutive singleton pregnancies with complete follow-up were included. High-risk women for PE/FGR were selected by combining data from maternal history and second trimester uterine artery Doppler. Subsequently these patients underwent intensive monitoring, including the measurement of the sFlt-1/PlGF ratio at 24-28 weeks to predict PE/FGR.

MAIN OUTCOME MEASURES: Early, intermediate and late PE/FGR (delivery <32 + 0, 32 + 0 - <36 + 0 and ≥36 + 0 weeks, respectively).

RESULTS: Overall incidence of early, intermediate and late PE/FGR was 0.3%, 0.7% and 3.2%, respectively, being higher in the 4.3% of women selected for intensive monitoring: 5.8%, 8.7% and 15.4%, respectively (all p < 0.001). The area under the curve (AUC) with 95%CI of the sFlt-1/PlGF ratio for detecting early PE/FGR was 0.98 (0.97-1.00), and the sFlt-1/PlGF ratio >95th centile showed a sensitivity (%) of 100 (95%CI, 78.5-100) and specificity (%) of 80.6 (95%CI, 75.0-85.2). The AUC of the sFlt-1/PlGF ratio for detecting intermediate and late PE/FGR was of 0.87 (95%CI, 0.77-0.97) and 0.68 (95%CI, 0.58-0.79), respectively.

CONCLUSION: A contingent strategy of measuring the sFlt-1/PlGF ratio at 24-28 weeks in women previously selected by clinical factors and uterine artery Doppler enables an accurate prediction of PE/FGR. This performance is optimal to predict PE/FGR requiring delivery before 32 weeks.