Use of the sFlt-1/PlGF ratio in the detection of preeclampsia. A systematic review and meta-analysis of prospective studies.

Objective: To evaluate the diagnostic accuracy of the sFlt-1/PlGF ratio as a screening test for the detection of preeclampsia. Methodology: A systematic review and meta-analysis were conducted following the PRISMA-DTA guidelines. The protocol was registered in PROSPERO under the code CRD42024601947. The search was performed in the Scopus, Web of Science, and EBSCO databases, and in the PubMed search engine, up to October 2024, including prospective studies that evaluated the sFlt-1/PlGF ratio in pregnant women without signs or symptoms of preeclampsia at the time of testing. Data were analyzed to calculate sensitivity, specificity, likelihood ratios, and heterogeneity. Methodological quality was assessed using QUADAS-2, and the certainty of the evidence was evaluated using GRADE. Results: Six prospective studies were included, with an estimated sensitivity of 66% and specificity of 84%. Heterogeneity was significant, with an I² of 83% for sensitivity and 99.8% for specificity. The predictive ability of the ratio was higher in the third trimester (sensitivity 65%, specificity 87%) and showed better results in early-onset preeclampsia (sensitivity 94.3%, specificity 81.7%). Conclusions: The sFlt-1/PlGF ratio has limited utility as a screening test for preeclampsia, with variable sensitivity and specificity across studies. Its effectiveness is greater in specific populations and in early-onset preeclampsia, but its application as a universal screening test is limited due to the heterogeneity among studies and variability in cut-off points.