Abstract
Placental biomarkers have been studied extensively for their role in development and progression of preeclampsia. Two biomarkers in particular, soluble fms-like tyrosine kinase (sFlt-1) and placental growth factor (PlGF), are part of the angiogenic profile of preeclampsia and serve as a useful measure for placental dysfunction. Alterations in their level are responsible for the pathophysiology of preeclampsia, and their measurements can help predict and predate clinical signs and symptoms of preeclampsia, allowing for risk assessment and escalation in care. Given that these biomarkers measure placental dysfunction, it is reasonable to suspect that they may be useful in the prediction of other placentally derived disease processes, such as fetal growth restriction and adverse neonatal outcomes. Recent studies have shown that low plasma PlGF in maternal serum is more reliable in distinguishing fetal growth restriction secondary to placental dysfunction versus constitutionally small fetuses when compared to typical ultrasound indicators such as abdominal circumference and umbilical artery doppler studies. Altered PlGF has predicted adverse neonatal outcomes, such as development of bronchopulmonary dysplasia and even perinatal deaths. High cord blood levels of sFlt-1 have been shown to correlate with degree of neonatal thrombocytopenia, indicative of endothelial disruption in the newborn. In the era of personalized and precision medicine, placental biomarkers may assist in triaging fetal surveillance and delivery, as well as neonatal care. This review covers the known pathophysiology of these biomarkers, our current understanding of their signaling pathways and downstream effects and includes recent research in their association with a significant complication of prematurity - bronchopulmonary dysplasia.