Complex congenital malformations and the impact of the plasminogen activator system and β-hCG in amniotic fluid
Objective: The plasminogen activator system and β-hCG may affect neural crest cells and angiogenesis, and thereby embryogenesis. Therefore, we investigated these parameters in amniotic fluids of pregnancies with a complex congenital malformation. Study design: In a case-control study amniotic fluid samples were collected from 62 pregnancies with a complex congenital malformation and from 110 healthy control pregnancies at an obstetric department of a large university hospital in the Netherlands. We determined concentrations of tissue-type plasminogen activator (tPA), urokinase-type plasminogen activator (uPA), plasminogen activator inhibitors (PAI-1, PAI-2), tPA∼PAI-1 and uPA∼PAI-1 complexes, and β-hCG with enzyme-linked immunosorbent assays. Mann-Whitney U-tests and analysis of covariance, adjusting for gestational and maternal age, were performed for data comparisons. Results: Compared with controls, cases demonstrated significantly lower adjusted geometric mean levels of uPA (24%), tPA (≥19%) and tPA∼PAI-1 (35%). Cases showed significantly higher adjusted mean levels of β-hCG (≥48%) and PAI-2 (10 ng/mL) than controls. Mean PAI-1 and uPA∼PAI-1 levels were comparable between both groups. Conclusions: Disturbances in the plasminogen activator system and β-hCG levels are suggested to be involved in the pathogenesis of complex congenital malformations by affecting neural crest cell migration and angiogenesis.