Plasma fibronectin was determined during normal pregnancy after 15th week, post partum, in cord blood and in cases of EPH gestosis. Non-pregnant women of a comparable age group were examined for plasma fibronectin concentration. Fibronectin at the end of gestation was at about the same level as at the beginning of the second trimester and as in non-pregnant women. The amount of fibronectin remains post partum practically the same. Cord blood fibronectin was about half the concentration of that in adult plasma. In EPH gestosis, levels were significantly elevated.