Fetal fibronectin levels are elevated in maternal plasma and amniotic fluid of patients with severe preeclampsia

OBJECTIVE: Our purpose was to investigate levels of fetal fibronectin in maternal plasma, amniotic fluid, and umbilical cord plasma from patients with severe preeclampsia. STUDY DESIGN: The study group comprised 20 patients with severe preeclampsia (group A). An antopartum comparison group was composed of 20 healthy patients matched for gestational age (group B). An intrapartum control group consisted of 20 term normotensive patients (group C). Maternal plasma samples were collected before labor (groups A and B), then immediately after delivery, and again at 20 to 24 hours post partum (groups A and C). Amniotic fluid was also collected in early labor, and umbilical cord blood was collected at delivery (groups A and C). Samples were assayed for fetal fibronectin by a specific enzyme-linked immunoassay. RESULTS: Before labor maternal plasma levels of fetal fibronectin were significantly elevated in preeclamptic patients compared with patients in group B (p < 0.0001). Plasma levels of fetal fibronectin were also increased in preeclamptic patients compared with patients in group C at delivery (p < 0.0001) and post partum (p < 0.05). Additionally, amniotic fluid levels of fetal fibronectin in the preeclamptic patients were significantly increased (p < 0.05). In contrast, umbilical cord plasma fetal fibronectin concentrations from the preeclamptic and control patients were similar. CONCLUSIONS: Fetal fibronectin is elevated in the maternal plasma and amniotic fluid, but not umbilical cord plasma, of patients with severe preeclampsia. These findings suggest an increase in production of fetal fibronectin from chorionic trophoblasts in patients with preeclampsia or an abnormal interaction between chorionic trophoblast and decidua with reusltant increased leakage into the maternal circulation and amniotic fluid.