Effect of meconium on the strength of chorioamniotic membranes.

A population of 1320 patients was reviewed to assess the clinical significance of antepartum meconium staining on the occurrence of premature rupture of the membranes. Specimens of amniotic membranes were studied by tensile strength testing from 2 population groups. The results of the retrospective review showed no difference in the incidence of premature rupture of the membranes between the populations with clear amniotic fluid and those with meconium-stained fluid at time of amniorrhexis. The tensile strength testing demonstrated that the study population with antepartum meconium-stained fluid had significantly lower stress tolerance. This investigation demonstrated a significant decrease in stress tolerance of human chorioamniotic membranes associated with a meconium-stained fluid environment, but this loss of stress tolerance is not apparently significant in clinical practice.