The overall incidence of cleft palate with or without cleft lip is 1 case in 1000 live births. The incidence of cleft palate varies by race, with the highest rate among American Indians, at 3.6 cases per 1000 live births, and the lowest rate among African Americans, with 0.3 cases per 1000 live births. Among the total number of clefts, 20% are an isolated cleft lip (18% unilateral, 2% bilateral), 50% are a cleft lip and palate (38% unilateral, 12% bilateral), and 30% are a cleft palate alone. The incidence of isolated cleft palate (without cleft lip) is 1 case in 2000 live births. Submucous cleft palate is more common, with an incidence of 1 case in 1200-2000 patients, depending on the study population. Bifid uvula occurs in 1 of 80 patients and often occurs in isolation, with no clefting of the palatal muscles.
No racial predilection exists for cleft palate, with an equal incidence among all races. Although cleft lip and palate together occur more commonly in males, isolated cleft palate is more common in females.
