Trisomy 18, also known as Edwards syndrome, is a chromosome disorder where a baby has 3 copies of chromosome 18 instead of the usual 2 copies. This extra genetic material affects growth and development and often causes heart defects, abnormalities of other organs, a small head and mouth, and clenched fists. Most babies with Trisomy 18 will die before or shortly after birth, though a small number may survive past 1 year, usually with severe intellectual disabilities. It occurs in about 1 in 5,000 live births and risk increases with maternal age.

1. Trisomy 18
EDWARDS SYNDROME

2. TRISOMY 18
Trisomy 18 also known as Edwards Syndrome
is a chromosome disorder characterized by
having 3 copies of chromosome 18 instead of
the usual 2 copies. The extra genetic material
disrupts the normal course of development,
causing the characteristic features of trisomy
18. Edwards' syndrome affects how long a
baby may survive. Sadly, most babies with
Edwards' syndrome will die before or shortly
after being born.
A small number (about 13 in 100) babies born
alive with Edwards' syndrome will live past
their 1st birthday.

3. A baby with Edwards' syndrome has 3 copies of chromosome
number 18 instead of 2. This affects the way the baby grows and
develops. Having 3 copies of chromosome 18 usually happens by
chance, because of a change in the sperm or egg before a baby is
conceived. Trisomy 18 results from defects in the mother's eggs
in 90 percent of its cases; further, the incidence rate increases
with maternal age.
Trisomy 18 occurs in about 1 in 5,000 live-born infants; it is more
common in pregnancy, but many affected fetuses do not survive
to term. 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.

4. This chromosomal condition associated with abnormalities in
many parts of the body. Individuals with trisomy 18 often have
slow growth before birth (intrauterine growth retardation) and a
low birth weight. Affected individuals may have heart defects
and abnormalities of other organs that develop before birth.
Other features of trisomy 18 include a small, abnormally shaped
head; a small jaw and mouth; and clenched fists with overlapping
fingers. Due to the presence of several life-threatening medical
problems, 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, and these children often have
severe intellectual disability.

5. TRISOMY 18 (EDWARDS SYNDROME)

7. Other Names for This Condition
(Trisomy 18/Edwards Syndrome)
Complete Trisomy 18 Syndrome
Edwards Syndrome
Trisomy 18 Syndrome
Trisomy E Syndrome