Which of the following shows lowest frequency of cleft lip and palate?
High-Yield Explanation
The incidence of cleft lip and palate is 1:600 live births and of isolated cleft palate is 1:1000 live births. The incidence increases in Oriental groups (1:500) and decreases in the black population (1:2000). The highest incidence reported for cleft lip and palate occurs in the Indian tribes of Montana, USA (1:276).
Although cleft lip and palate is an extremely diverse and variable congenital abnormality, several distinct subgroups exist, namely cleft lip with/without cleft palate (CL/P), cleft palate (CP) alone and submucous cleft palate (SMCP).
The typical distribution of cleft types is:
Cleft lip alone: 15%;
Cleft lip and palate: 45%;
Isolated cleft palate: 40%.
Cleft lip/palate predominates in males, whereas cleft palate alone appears to be more common in females. In unilateral cleft lip the deformity affects the left side in 60% of cases.
Key Concept:
The incidence increases in Oriental groups (1:500) and decreases in the black population (1:2000). The highest incidence reported for cleft lip and palate occurs in the Indian tribes of Montana, USA (1:276).
Reference: Bailey & Love’s short practice of surgery , 27th ed page no 688