Trisomy 18

1. Trisomy 18

2. What is it? • Edwards syndrome (also known as Trisomy 18 [T18]) • Is a genetic disorder, chromosomal disease 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.

3. Who does it effect? And what is the life expectancy? • It is genetic. • Edwards syndrome occurs in around one in 6,000 live births and around 80 percent 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.

4. What are the Signs and Symptoms? • Kidney malformations, structural heart defects at birth, intestines protruding outside the body, esophageal atresia, mental retardation, developmental delays, growth deficiency, feeding difficulties, breathing difficulties • Physical: small head, low- set malformed ears, abnormally small jaw, cleft lip/ cleft palate, unturned noise, drooping of the upper eyelids, short breast bone, clenched hands, choroid plexus cysts, undeveloped thumbs and or nails, absent radius, webbing of toes, undescended testicles.

5. Prognosis • In 2008/2009, there were 495 diagnoses of Edwards syndrome. • There were 339 abortions, 49 stillbirths/ miscarriages/ fetal deaths, 72 unknown outcomes, and 35 live births. • Because approximately 3% of cases with unknown outcomes are likely to result in a live birth, the total number of live births is estimated to be 37 (2008/09 data are provisional) • Major cause of death- apnea and heart abnormalities. • 50% of babies who are carried to term will be still born. • Less than 10 percent survive to the first birthday.

6. What is the treatment? • Treatment for trisomy 18 is supportive, meaning that the condition cannot be cured, and treatments are directed at prolonging survival and managing complications. Common treatment measures include nutritional support, treatment of infections, transfusions for low blood cell counts, and medications such as diuretics and/or digoxin to manage heart failure. Heart failure and pneumonia are common causes of death in people with trisomy 18. • REMEMBER: There is such thing as a False positive result in the genetic testing. False testing • OPTIONS: Abortion is an option, but if you are against abortion there this a 50 percent chance your child will live until they are one. Also, the 10 percent chance of the half that would live have lived to mid 20s.