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Healthcare provider resources
Discover an extensive library of publications, educational materials, and other tools supporting the PreClara Ratio (sFlt-1/PlGF) for preeclampsia risk stratification.
Clinical studies and evidence
Chan et al., 2018
Analytical validation of soluble fms-like tyrosine and placental growth factor assays on B·R·A·H·M·S KRYPTOR Compact Plus automated immunoassay platform
Espinoza et al., 2024
Plasma soluble fms-like tyrosine kinase 1 to placental growth factor ratio of 11.5 multiples of median predicts preeclampsia with severe features within 2 weeks of testing
Espinoza et al., 2024
Plasma soluble fms-like tyrosine kinase 1 to placental growth factor ratio of 11.5 multiples of median predicts preeclampsia with severe features within 2 weeks of testing
Thadhani et al., 2022
Circulating angiogenic factor levels in hypertensive disorders of pregnancy
Azzi et al., 2025
Neonatal cost savings in hypertensive disorders of pregnancy: Economic evaluation of the sFlt-1/PlGF test with real world implementation of biomarkers.
Rana et al., 2022
Imbalances in circulating angiogenic factors in the pathophysiology of preeclampsia and related disorders
Levine et al., 2004
Circulating Angiogenic Factors and the Risk of Preeclampsia
Guidance
ACOG Clinical Practice Update. June 2024
Biomarker Prediction of Preeclampsia With Severe Features. Obstetrics & Gynecology
The American College of Obstetricians and Gynecologists (ACOG) advises that “If the sFlt-1:PlGF ratio is used for hospitalized patients admitted between 23 and 35 weeks of gestation with hypertensive disorders, the test is a complementary risk stratification screen to add to the diagnostic work-up of preeclampsia with severe features.”
On-demand education
Case studies
Product literature
Additional resources and media coverage
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