FIBRINOLYTIC COMPONENTS IN FETAL MEMBRANES AND AMNIOTIC-FLUID

OBJECTIVE: We evaluated fibrinolytic components in plasma and amniotic fluid of pregnant women and in postpartum fetal membranes. STUDY DESI GN: Fibrinolytic parameters in amniotic fluid and plasma were measured by means Of enzyme-linked immunosorbent assays. Fetal membranes colle cted after spontaneous labor at term were analyzed by immunohistochemi cal methods with immunospecific antibodies against fibrinolytic compon ents. RESULTS: Amniotic fluid contained high plasminogen activator inh ibitor-1 concentrations but had low activity. Strong staining for plas minogen activator inhibitor-1 and vitronectin was observed in chorioni c trophoblasts and moderate staining in decidual connective tissue. St rong staining for plasminogen activator inhibitor-2 was seen in decidu al cells. Although prominent staining of plasminogen activators and pl asminogen were observed in the amniotic epithelium, virtually no plasm inogen activator inhibitor-1, plasminogen activator inhibitor-2, or al pha2-plasmin inhibitor staining was detected. CONCLUSION: The delicate balance of fibrinolytic activators and inhibitors in fetal membranes and amniotic fluid may contribute to the triggering of membrane ruptur e at term.