About Cleft Lips & Palates

What is a Cleft?

A "cleft" is the medical term for a separation which canoccur in the lip or the palate (roof of the mouth), or both. Thecleft may be as minor as a notch in the upper lip or as extensiveas a wide fissure extending through the lip and gum into the nose.The cleft may occur on one side of the lip (unilateral cleft lip)(Figure 1) or on both sides of the lip (bilateral cleft lip) (Figure2). A cleft palate may occur in combination with a unilateral orbilateral cleft of the lip or may occur with a completely normallip. 

How Common areCleft Lips and Palates?

Clefts of the lip and palate are the most common congenital deformityaffecting the face. The overall frequency is approximately one inevery six hundred births. It is more common in children of Asiandescent, occurring in approximately one in every five hundred births,and least common in black children, occurring in approximately onein every two thousand births.

What is the Causeof Cleft Lip and Palate?

Clefts arise when the lip and mouth do not come together properlyin fetal development. Actually, each of us had clefts of the lipand palate before birth which normally fuse so that the clefts arenot present at birth. No one knows exactly why clefts occur, althoughthey do run in families to some extent. If one parent or child ina family has a cleft, the chances of a subsequent child being bornwith a cleft increases from the usual one in six hundred to approximatelyone in twenty. Because there are some circumstances in which therisk is even higher, it is important to meet with a geneticist tofind out the approximate risk in any particular family. Parentsshould also understand that they have done nothing wrong duringthe pregnancy to cause the cleft. Nothing a woman eats or drinks,no medications she may have taken, nor any activities she has participatedin while pregnant have any known effect on this particular birthdefect. Parents with the most carefully monitored, trouble freepregnancies give birth to children with clefts at the same rateas the rest of the population.