MPFD is caused by<unk>  fibrous tissue around the chorionic villi of the placenta. The placenta often shows lesions upon histology and autopsy. The villi become trapped, causing avascular necrosis. This causes reduced substance exchange, and movement of the placenta. This can cause reduce growth of the foetus, and may lead to miscarriage.
Massive perivillous fibrin deposition
Collagenous spherulosis
Nodular vasculitis
Cerebroretinal microangiopathy with calcifications and cysts
Reactive perforating collagenosis
Platelet-rich fibrin matrix
Granulovacuolar degeneration
Palisaded neutrophilic and granulomatous dermatitis