Detection of angiogenic factors in midtrimester amniotic fluid and the prediction of preterm birth

Abstract Objective We investigated whether the level of vascular endothelial growth factor (VEGF), placental growth factor (PlGF), and soluble VEGF receptor-1 (sFlt-1) in midtrimester amniotic fluid of preterm birth have different values compared with term delivery. Materials and Methods Our participants were 86 pregnant women who had undergone amniocentesis from 16 to 19 weeks of gestation. Forty-three cases were women with preterm delivery, and the other 43 cases were matched women with full-term delivery. Stored amniotic fluid was investigated after the delivery. The levels of VEGF, PlGF, and sFlt-1 were measured by enzyme-linked immunosorbent assay and Western blot. Results The levels of VEGF and PlGF in the preterm group were significantly higher than in the control group (30.48 ± 8.57 pg/mL vs. 26.06 ± 8.24 pg/mL and 28.83 ± 7.83 pg/mL vs. 25.35 ± 8.26 pg/mL, respectively) ( p  = 0.017 and 0.048, respectively). In terms of sFlt-1, the levels were decreased in the preterm group (10,478.51 ± 4012.56 pg/mL vs. 12,544.05 ± 4140.96 pg/mL) ( p  = 0.021). Conclusion This study explains that elevated levels of VEGF and PlGF, suggestive of angiogenesis and tendency of inflammation at midtrimester, are predictive of preterm delivery, and their availability is maximized by downregulation of sFlt-1.