A congenital diaphragmatic hernia (CDH) presents a hole in the fetal diaphragm muscle, allowing the intestines, stomach, liver and other abdominal organs to enter the chest, compressing the lungs and restricting fetal lung development. In this video Dr. Ahmet Baschat, director of the Johns Hopkins Center for Fetal Therapy, presents footage from a minimally invasive procedure called fetoscoptic tracheal occlusion (FETO) that can improve the postnatal lung function for fetuses with severe CDH.