|
|
What is a
cleft?
- A "cleft"
is the medical term for a failure of the upper lip and/or palate
(roof of the mouth) to fuse as normally takes place between the
5th and 12th week of pregnancy.
- The cleft
may be as minor as a notch in the upper lip or as extensive as
a wide gap extending through the lip and gum into the nose.
- The cleft
may occur on one side of the lip (unilateral) or on both sides
of the lip (bilateral).
- A cleft palate
may occur in combination with a unilateral or bilateral cleft
of the lip or may occur with a completely normal lip.
- Clefting
can occur on other parts of the face as well.
How common
is cleft lip and palate?
- Clefts of
the lip and palate are the most common congenital deformity affecting
the face.
- The overall
frequency of clefts is approximately one in every six hundred
births.
- Clefting
is more common in children of Asian descent, occurring in approximately
one in every five hundred births, and least common in African
American children, occurring in approximately one in every two
thousand births.
What is the
cause of cleft lip and palate?
- Clefts arise
when the lip and mouth do not come together properly in fetal
development.
- No one knows
exactly why clefts occur, although there may be a predisposition
in some families. If one parent or child in a family has a cleft,
the chances of a subsequent child being born with a cleft increases
from the usual one in six hundred to approximately one in twenty.
Because there are some circumstances in which the risk is even
higher, it is important to meet with a geneticist to find out
the approximate risk in any particular family.
- Parents should
also understand that they have done nothing wrong during the pregnancy
to cause the cleft. Parents with the most carefully monitored,
trouble free pregnancies give birth to children with clefts at
the same rate as the rest of the population.
|
|
