In the early weeks of development, long before a child is born, the right and left sides of the lip and the roof of the mouth normally grow together. Occasionally, however, in about 1 in every 800 babies, these sections do not quite meet.
A child born with a separation in the upper lip is said to have a cleft lip. A similar birth defect in the roof of the mouth, or palate, is called a cleft palate. Since the lip and palate develop separately, it is possible for a child to have a cleft lip, a cleft palate, or variations of both.
If a child is born with either or both of these conditions, most often surgery is recommended to repair it.