Plasmodium falciparum-infected erythrocytes adhere both in the intervillous space
and on the villous surface of human placenta by binding to the low-sulfated chondroitin sulfate proteoglycan receptor.
The increased turbulence in the intervillous space
may damage the syncytium and increase perivillous fibrin deposition, so both the chronic injury of the perfusion of the placenta and/or nutritional deprivation could eventually lead to impaired development of the villi (5).
Within the intervillous spaces
, many of the maternal red blood cells were sickle shaped (Figures 1 and 2).
The thickness increases during contraction due to distension of intervillous spaces
by maternal blood.
We recently reported that fetal DNA in maternal plasma is derived primarily from villous trophoblasts bordering the intervillous spaces, which are filled with maternal blood (13).
Because there is insufficient invasion of extravillous trophoblasts into the uterine vasculature, placental vascular resistance is not reduced; there thus is inadequate oxygenation of blood within the placental intervillous spaces that border villous trophoblasts.