An expectant mother's prenatal ultrasound exam indicates a possible abnormality in the fetus. A follow-up MRI reveals that the baby's diaphragm -- the membrane separating the lungs from the visceral organs -- has a hole in it, large enough that the intestines have grown into the chest cavity. This condition, called congenital diaphragmatic hernia, causes the lungs to be crowded and compressed so they cannot grow normally. The baby must have this hole patched soon after birth.