Variation in composition of the intervillous space lining in term placentas of mothers with pre-eclampsia.

To define composition of chorionic plate and test effects of pre-eclampsia on basal plate composition. Retrospective cohort study where distinct area fractions were measured in: healthy term chorionic plate (CP: n = 11), healthy placental basal plate (n = 11), mild pre-eclamptic basal plate (n = 10) and severe pre-eclamptic basal plate (n = 11). CP lining is partly endothelial. Mean anchoring villus (AV)/acellular (NS) basal plate area ratio decreased in pre-eclampsia (p = 0.048). There was a decreasing trend with increasing disease severity. Basal plate endothelial cell proportion was not significantly lower in severe pre-eclampsia than in healthy or mild pre-eclamptics. An inverse relationship between the proportions of fibrin and anchoring villi indicates that increased basal plate fibrin deposition and reduced basal plate materno-fetal anchoring area are part of pre-eclamptic disease progression. Endothelium lining intervillous surfaces may originate from circulating maternal endothelial progenitor cells.