A multicenter study led by researchers from the Sant Pau Research Institute (IR Sant Pau) and the Department of Obstetrics and Gynecology at Hospital de Sant Pau has shown that the NT-proBNP biomarker—commonly used to rule out heart failure in non-pregnant patients—can reliably predict the onset of early-onset preeclampsia (before 34 weeks of gestation), with a sensitivity of 90.9% and a specificity of 94.3%. These results are comparable to those of the currently used test (the sFlt-1/PlGF ratio), but with the advantage of being more affordable and widely available. The study was conducted in a group of 316 pregnant women with clinical suspicion of preeclampsia between 24 and 40 weeks of gestation.
According to Dr. Carmen Garrido, Head of Obstetrics at Hospital Sant Pau and collaborating researcher with the Perinatal and Women’s Medicine group at IR Sant Pau, “Preeclampsia is a disease that affects the cardiovascular system and is often associated with subclinical heart dysfunction during pregnancy. We knew from the literature that women with preeclampsia tend to have elevated levels of this biomarker. That led us to consider that NT-proBNP might be useful in predicting short-term complications, especially in settings without access to the sFlt-1/PlGF test.”
Dr. Madalina Nicoleta Nan, also a researcher with the Perinatal and Women’s Medicine group, adds: “The study suggests NT-proBNP is a valuable biomarker for ruling out the onset of preeclampsia at the time of suspicion and up to a week after assessment, especially in cases where the currently recommended test is unavailable.”
This prospective study, published in Ultrasound in Obstetrics & Gynecology, was conducted between March 2018 and December 2020. It provides a practical and reliable tool to support personalized prediction and management of pregnant women with suspected preeclampsia in the second or third trimester, after first-trimester screening. In this context, NT-proBNP can help rule out short-term preeclampsia—within one week—particularly in resource-limited settings.
NT-proBNP, a protein associated with cardiac stress, is already routinely used to diagnose heart failure in the general population. In pregnancy, this biomarker reflects cardiovascular changes in women with preeclampsia and correlates with disease severity.
According to the study, NT-proBNP levels rise significantly days before symptom onset, making it an early warning marker. This predictive capability opens the door to enhanced clinical monitoring in at-risk women and the implementation of preventive measures, such as corticosteroids for fetal lung maturation or hospital admission if needed.
Dr. Garrido explains, “the main advantage of NT-proBNP is that it allows for objective and rapid assessment in settings where the sFlt-1/PlGF ratio is unavailable. This could help avoid unnecessary referrals to specialized centers and promote greater equity in care.”
Although the sFlt-1/PlGF test is very effective for ruling out the disease (a low value excludes preeclampsia with 99% reliability), its positive predictive value is more uncertain, which can complicate clinical decision-making. The study suggests that NT-proBNP may offer improved precision in this scenario. “Our aim was to determine whether this biomarker could refine our predictions and support more conservative clinical decisions as pregnancy nears term,” adds Dr. Nan.
Beyond predicting early-onset preeclampsia, NT-proBNP also proved useful for identifying complicated cases associated with fetal growth restriction, placental abruption, or fetal death. Its predictive performance in this regard was similar to that of the current test.
Its sensitivity for predicting these serious complications was 84.2%, with a specificity of 91.4%—results comparable to the sFlt-1/PlGF test. This opens the door to broader clinical use. An integrated approach could be especially relevant in obstetric pathology or intermediate care units, where anticipating complications can significantly affect maternal and fetal outcomes.
This study provides the first evidence that NT-proBNP can predict disease before symptoms appear, paving the way for a new line of research already underway. The same team is now conducting a follow-up study to see whether combining this biomarker with the sFlt-1/PlGF ratio could further enhance predictive performance.
Even so, the researchers emphasize the need for larger, randomized studies before any changes are made to standard clinical practice. For now, the use of NT-proBNP should be limited to cases with clinical suspicion of preeclampsia, and results should always be interpreted in the context of specialized medical assessment. “This discovery allows us to move toward more equitable medicine, by offering a highly reliable diagnostic tool that does not require specialized technology,” says Dr. Garrido. “Moreover, its use could be particularly relevant in international settings with limited healthcare systems, helping reduce maternal morbidity and mortality in countries with less access to advanced diagnostic tools.”
M. N. Nan; C. Garrido-Giménez; A. Garcia-Osuna; P. Garcia Manau; J. Ullmo; J. Mora; O. Sánchez-Garcia; J. Platero; M. Cruz-Lemini; E. Llurba; on behalf of the EuroPE working group. N-terminal pro B-type natriuretic peptide as biomarker to predict pre-eclampsia and maternal-fetal complications. Ultrasound Obstet Gynecol 2025; 65(4):447–455. DOI: 10.1002/uog.29202
