- Thanks to prenatal ultrasound, esophageal atresia and intestinal obstruction has been diagnosed earlier and time calling for surgery of esophageal atresia, duodenal atresia, intestinal obstruction and gastrointestinal tract malformations generally has been taken earlier than the group without prenatal diagnosis - The Thesis has associated congenital malformations in gastrointestinal tract diagnosed in 3 branches: Obstetrics, Pediatrics and Surgery.