Soluble vascular endothelial growth factor receptor-1 (sFlt-1) is increased throughout gestation in patients who have preeclampsia develop.

This study was undertaken to analyze prospectively circulating vascular endothelial growth factor (VEGF) and its soluble receptor, (s) Flt-1, throughout normotensive and preeclamptic pregnancies and to assess the importance of these proteins in the development of preeclampsia. In this longitudinal cohort study, serum samples were collected from recruited subjects throughout pregnancy at 12, 20, 30, and 37 weeks and in the 24 hours before and after delivery. Subjects were divided retrospectively into normotensive and preeclamptic groups. Circulating VEGF and sFlt-1 concentrations were analyzed by radioimmunoassay and enzyme-linked immunosorbent assay, respectively. Circulating sFlt-1 and VEGF significantly increased as gestation progressed and both were further elevated in preeclampsia compared with normotensive pregnancy. Soluble Flt-1 concentrations were elevated early in gestation and were significantly increased at 30 weeks' gestation in those who subsequently developed preeclampsia. These results indicate a definite association between elevated sFlt-1 concentrations and the onset of preeclampsia suggesting that sFlt-1 is linked with disease pathogenesis.