Edwards' Syndrome

Trisomy 18


Trisomy 18, commonly known as Edwards' Syndrome, is a genetic disorder linked to autosomal chromosome 18. The disorder is caused by a person having an extra copy of chromosome 18. This is mainly caused by nondisjunction. There are different ways the trisomy 18 error can occur, however. Some can be inherited while others are genetic. Mosaic trisomy 18 is not inherited. Mosaic nondisjunction is the failure of the chromosome pairs to separate from each other during meiosis, causing both chromosomes to go to a single daughter cell ("Meiotic Nondisjunction"). Nondisjunction occurs randomly as eggs and sperm are formed. It occurs during cell division early in embryonic development. Partial trisomy 18 can be inherited. An unaffected person can carry a rearrangement of genetic material between chromosome 18 and another chromosome. Although they do not have signs of trisomy 18, people who carry this are at an increased risk of having children with the condition ("Trisomy 18"). There are numerous health-related concerns and physical symptoms related to trisomy 18. These include heart defects, kidney problems, delayed growth, severe developmental delays, small jaw and head, and rocker bottom feet ("Trisomy 18 Foundation"). It is possible to live with Edwards' Syndrome. Those with the syndrome continue to live happily into adulthood and are extremely active in their communities.

Life Past Birth

Trisomy 18 is most commonly found infants because many of those affected do not live past infancy. Trisomy 18 occurs in about 1 in 6,000 live-born infants. However, it is more common in pregnancy. It is seen in about 1 out of every 2500 pregnancies. Unfortunately, many affected fetuses do not survive ("Trisomy 18 Foundation"). Although women of all ages can have a child with trisomy 18, the chance of having a child with this condition increases as a woman gets older ("Trisomy 18"). Trisomy is three times more likely to occur in females than males. However, females are also more likely to survive with this disease, and survival rates are similar for all ethnic groups. Intensive care admissions in Neonatal Intensive Care Units are routine for newborn infants with Trisomy 18. Baby boys will experience higher mortality rates in this neonatal period than baby girls. Those with higher birth weights have a better chance of survival across all categories ("Trisomy 18 Foundation"). Several life-threatening medical problems cause many individuals with trisomy 18 die before birth or within their first month. Five to 10 percent of children with this condition live past their first year. However, these children often have severe intellectual disabilities ("Trisomy 18") . The infants that are able to survive are discharged from the hospital with home nursing support to assist the parents with care for the child. Although 10 percent or more may survive to their first birthdays, there are children with Trisomy 18 that can enjoy many years of life with their families, reaching important life events and being involved with their community. A small number of adults (usually girls) with Trisomy 18 can live into their twenties and thirties. However, significant developmental delays do not allow them to live independently, and they must rely on full-time caregiving ("Trisomy 18 Foundation").

Symptoms and Health Probelms

Individuals with trisomy 18 often have slow growth before birth and a low birth-weight. Those affected may have heart defects and other deformed organs that develop before birth ("Trisomy 18"). Common problems associated with Trisomy 18 can include: heart defects, kidney problems, clenched hands, rocker bottom feet, delayed growth, small jaw, small head, low-set ears, strawberry-shaped head, and severe developmental delays ("Trisomy 18 Foundation").

Treatments for Trisomy 18

There are no specific treatments for trisomy 18. Treatments are used depending on the person's individual condition ("MedlinePlus - Health Information from the National Library of Medicine"). However, those with trisomy 18 can be given supportive medical care to help give those affected the best quality of life possible. The affected can be very active in their communities, and live a very enjoyable life.