[Plasma fibronectin: influence of age and sex].

The aim of this study was to determine, first, the effect of sex and age on the results of plasma fibronectin (Fn), and also the possible influence of the gestational age. The plasma Fn concentrations are higher in men than in women only in a range of 15-29 years old. The age dependence is very strong on plasma Fn levels; it practically double during life.