In a

34-year-old pregnant woman, an elective caesarean section is necessary. The

cause is the diagnosis of placenta increta, which was already discovered during

regular screening checks. After the baby is born, a hysterectomy (removal of

the uterus) is performed with the placenta attached. Placenta increta is a

condition in which the main placental villi grow deep into the uterine

myometrial musculature. What is the maternal part of the placenta called?