Pathologic placental invasion is an increasing problem in the industrial world due to rising caesarean section rates. The aim of this project is to combine the knowledge of the faculty to allow a holistic analysis of this pathology combining histology, tissue culture work, and stem cells characterization to hopefully understand pathologic placental invasion better at the end of this project. Placenta creta is defined as a pathologic attachment of the placenta to the uterus. There is little doubt that the worldwide caesarean delivery epidemic has led to an increased incidence of abnormally adherent and invasive placentation, so called morbidly adherent placenta (MAP). The physiological separation of placenta from the uterus at time of delivery is impossible. This condition is associated with severe peripartum and postpartum haemorrhage and consecutively with maternal morbidities due to intraoperative complications. Manual removal of the placenta is often required and in severe cases like placenta increta or percreta hysterectomy is necessary. The risk for MAP is around 3% after one caesarean section and increases up to 60% in women with ≥ 4 caesarean sections. To date it is not clear which pathomechanisms are the underlying cause for the pathological placental invasion. Only few reports have been published regarding basic histological and immunological parameters in MAP . It seems that the lack of a functional decidua, dysregulated inflammatory reactions are likely to lead to pathological placentation caused by excessive trophoblast proliferation and invasion of the placenta into the uterine wall. Vascular abnormalities, uteroplacental underperfusion, decidual hemosiderosis and infarction, as well as acute or chronic inflammation have also been postulated as possible risk factors. To date, no paper reports a comprehensive analysis of MAP tissue combining histological, immunological and stem cell data. The aim is to find a correlation of histological, immunological and endometrial stem cell properties in MAP.