Figure 2.

Abnormal placentation occurring in oocyte donation pregnancies. Placental thrombomodulin expression is lower in OD pregnancies than in natural ones, independently from the occurrence of pre-eclampsia and this reduction can be responsible for different complications such as apoptosis in syncytiotrophoblasts, increased inflammation and coagulation that then lead to increased fibrin deposition, as confirmed by immunohistochemical staining.