Bacterial protease-induced reduction of chorioamniotic membrane strength and elasticity.

We demonstrated that in vitro exposure to bacterial collagenase and collagenase-producing microorganisms significantly reduces measures of strength (bursting load), elasticity, and work to rupture of human amniochorion in a dose-dependent fashion. An attenuated noncollagenase-producing stain did not alter these measures. These findings support previous suggestions that infection within the lower uterine segment adjacent to the cervix may mediate some instances of premature rupture of membranes.