Low molecular weight peptides with anti-thrombin and anti-urokinase activity isolated from human maternal and cord blood serum and amniotic fluid.

Peptides with antithrombin and anti-urokinase activity were isolated from maternal and cord blood serum and amniotic fluid from pregnant women at term. Chromatography data, fingerprinting and activity of peptide inhibitors revealed active peptides, which were similar to those recently isolated from human placenta. They are distinctly different from protein inhibitors previously isolated from human placenta.