Abdominal pregnancy is a form of "ectopic pregnancy" where the pregnancy grows outside it's normal place inside the abdomen instead of where it should grow inside the uterus

An abdominal pregnancy a rare and dangerous medical condition and especially if it's missed then it can threaten the mother's life. Abdominal pregnancy  is estimated to occur only about once in every 10,000 pregnancies. It begins when an embryo implants away from the uterus inside the abdominal cavity. 

Symptoms of abdominal pregnancy include normal pregnancy symptoms but in addition women experience unusual abdominal pain.

The diagnosis is made with ultrasound when the fetus is seen outside the uterus.

When abdominal pregnancy is identified early on termination of the pregnancy is usually advised. If detected later, the mother must be carefully monitored during pregnancy and after delivery. Delivery usually requires surgery. The placenta can adhere to vital organs such as the liver or bowel making removal life-threatening to the mother. Severe bleeding can occur before delivery and if the placenta is surgically removed when the baby is taken. As a rule, the placenta is left intact so the mother’s body can reabsorb it, a process that can take months and requires medical monitoring.