Collagen metabolism in premature rupture of amniotic membranes.

Collagen content, acid-soluble collagen, degradation activity, and collagen biosynthesis were measured in 22 normal and 20 prematurely ruptured membranes from pregnancies near term (37 weeks or more). Although no significant differences were found in the collagen content, a clear correlation was found between this value and the interval from premature rupture to delivery. Collagenolytic activity and collagen solubility were higher and collagen synthesis was lower in amniotic membranes that ruptured prematurely. These studies suggest that premature rupture of membranes is associated with extensive changes in collagen metabolism.