Edwards syndrome

Edwards syndrome (also known as trisomy 18 [T18]) is a chromosomal abnormality caused by the presence of all, or part of, an extra 18th chromosome. This genetic condition almost always results from nondisjunction during meiosis. It is named after John Hilton Edwards, who first described the syndrome in 1960. It is the second-most common autosomal trisomy, after Down syndrome, that carries to term.

Edwards syndrome occurs in around one in 6,000 live births, and around 80% of those affected are female. The majority of fetuses with the syndrome die before birth. The incidence increases as the mother's age increases. The syndrome has a very low rate of survival, resulting from heart abnormalities, kidney malformations, and other internal organ disorders.

Signs and symptoms

Children born with Edwards syndrome may have some or all of these characteristics: kidney malformations, structural heart defects at birth (i.e., ventricular septal defect, atrial septal defect, patent ductus arteriosus), intestines protruding outside the body (omphalocele), esophageal atresia, intellectual disability, developmental delays, growth deficiency, feeding difficulties, breathing difficulties, and arthrogryposis (a muscle disorder that causes multiple joint contractures at birth).