Advanced abdominal pregnancy: challenges, update and review of current management

Key content Although extremely rare, advanced abdominal pregnancy (AAP) is associated with considerable maternal and fetal morbidity and mortality. However, when diagnosed early and managed appropriately, it is possible to have successful outcomes. There are no specific criteria to diagnose AAP and it may be missed on ultrasound. Magnetic resonance imaging is the gold standard for evaluating placental implantation and preoperative planning. Management depends on the gestational age at diagnosis, with consideration of termination, preterm delivery and conservative management until further fetal maturation. Multidisciplinary preoperative planning is paramount for optimal outcome. Delivery is recommended in a tertiary centre with access to interventional radiology. Management of the placenta depends on the degree of penetration and the organ in which it embeds. Where the risk of removal increases the risk of maternal morbidity, it may be left in situ. Learning objectives To outline the classification of AAP. To understand the diagnostic challenges and the role of imaging in preoperative assessment. To describe the different management options and associated ethical issues. Ethical issues There is no established guidance for the diagnosis and management of AAP. AAP requires careful evaluation when deciding whether to terminate the pregnancy or provide expectant management. Informed consent requires acknowledgement of the considerable risks.