 Trisomy 18, also known as Edwards
syndrome, it is caused by a chromosome
defect.
 A trisomy is when a person is born with
three chromosomes instead of the normal
two chromosomes.
 So Trisomy 18 is when there is three 18
chormosomes.
Three number 18 Chromosomes
 Trisomy 18 is a relatively common
syndrome. It is three times more common
in girls than boys. The syndrome is
caused by the presence of extra material
from chromosome 18. The extra material
interferes with normal development
There are three different types of
Trisomy 18
 Full Trisomy 18: The most common type of Trisomy
18. It is when the extra chromosome occurs in every
cell in the baby's body.
 Partial Trisomy 18: very rare, they occur when only
part of an extra chromosome is present. This may be
caused by hereditary factors.
 Mosaic Trisomy 18: also very rare. This occurs when
the extra chromosome is present in some of the
cells of the body. However, this is not inherited and is
a random occurrence that takes place during cell
division.
 Just like a kid with Down syndrome can range
from mildly to severely affected, the same is true
for children with Trisomy 18. However, statistics
show that there is a high mortality rate for children
with Trisomy 18 before or shortly after birth.
 Fifty percent of infants with this condition do not
survive beyond the first week of life. Some
children have survived to the teenage years, but
with serious medical and developmental problems
Typical characteristics of Trisomy 18
 Kidney problems
 The esophagus doesn’t connect to the stomach
 Clenched hands
 Delayed growth
 Low-set ears
 Strawberry-shaped head
 Severe developmental delays
 Umbilical or inguinal hernia
Clenched Hands
Low-set ears