Lower placental growth factor and higher free β-hCG and PAPP-A levels in the fetal circulation of near-term pregnancies complicated with severe preeclampsia

Abstract

Background: An imbalance between anti- and angiogenic factors during early placentation is key for the development of preeclampsia. Nevertheless, the majority of studies addressing this issue relate to maternal blood and not the fetal circulation.Objective: To measure placental growth factor (PlGF), free beta human chorionic gonadotropin (β-hCG), and pregnancy-associated plasma protein-A (PAPP-A) levels in the fetal circulation of near-term pregnancies complicated with severe preeclampsia (n = 20), and their controls matched for parity, and maternal and gestational age.Method: Upon delivery, a blood sample was withdrawn from the umbilical artery and vein of each case and its control in order to measure the proposed analytes using direct fluoroimmunoassay.Results: Preeclampsia cases showed significantly lower median PlGF levels in fetal circulation as compared to controls (25.2 versus 36.9 and 23.6 versus 33.9 pg/mL, artery and vein, respectively, p < 0.05). Contrarily, cases displayed higher concentrations of PAPP-A (1024.0 versus 720.9 [median] and 1027.0 ± 298.4 versus 690.3 ± 401.9 mIU/L, artery and vein, respectively, p < 0.05), and free β-hCG (mean: 33.9 ± 4.3 versus 17.2 ± 4.0 and 30.1 ± 5.2 versus 13.7 ± 3.3 ng/mL, artery, and vein respectively, p < 0.05).Conclusion: Lower PlGF and higher PAPP-A and free β-hCG levels were found in the fetal circulation of near-term severe preeclamptic pregnancies. There is a need for more research in this regard.