Placental and decidual u-PA, t-PA, PAI-1 and PAI-2 concentrations, as affected by cervical dilatation with laminaria tents or Hegar dilators.

The effect of cervical dilatation on PA and PAI concentrations was compared in a laminaria tent group and a mechanical dilatation (control) group. In both groups, u-PA and t-PA were found to be present both in decidual and placental tissue. Values for PAI-1 in the decidua were higher in the laminaria tent group than in controls, and those for PAI-2 in the placenta were lower. These findings provide support for the contention that cervical dilatation with laminaria tents may result in partial detachment of the placenta.