Definition: An omphalocele is a birth defect in which an intestine or other abdominal organs are outside of the body because of a defect of the anterior abdominal wall. The content is covered by only a thin membrane and can be easily seen. 
Pathogenesis: Many theories have also been suggested to explain the development of omphalocele. These include failure of intestinal migration into the abdomen by 10 to 12 weeks of embryologic development, failure of central migration of the lateral body folds of mesoderm, and persistence of a body stalk beyond 12 weeks' gestation. 
Diagnosis and sonographic findings: omphalocele can be diagnosed by ultrasound in the late first trimester. This is due to the physiological herniation of the bowel into the umbilical cord during early fetal development.
Differential diagnosis: Differential diagnoses include gastroschisis, pseudo omphalocele, physiological gut herniation, limb-body wall complex and umbilical hernia.
Associated anomalies: omphalocele can be associated with congenital abnormalities like congenital heart disease; neural tube defects, and chromosomal abnormalities. 
Prognosis: the prognosis depends on the size of the defect, the presence of other abnormalities and the associated complications. 
Management: The management of omphalocele can only be finalised after birth and the medical team have assessed the baby for other associated abnormalities. Surgery is more challenging if the omphalocele is large.
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