 Between 25–60% of infants with a Bochdalek hernia die.The lungs, diaphragm, and digestive system are all forming at the same time, so when a Bochdalek hernia permits the abdominal organs to invade the chest cavity rather than remain under the diaphragm in the correct position, it puts the infant in critical condition.These "foreign bodies" in the chest cavity compress the lungs, impairing their proper development and causing pulmonary hypoplasia.