Abstract
A survey on cleft lip and/or palate incidence has been conducted on 343 obsterical and gynecological clinics for 1981 and 1982.
1. Incidence: From the 133,042 birth records,217 infants with cleft lip and/or palate were identified. The incidence was 0.163%.
2. The order of cleft frequency was lead by cleft lip and palate followed by cleft lip only and cleft palate only.
3. Sex ratio: All clefts were more frequent in male than in female.
4. Cleft side: Unilateral clefts were significantly predominant over bilateral ones, and left side clefts were significantly more frequent than right side ones.
5. Birth weight and period of gestation: The frequency of births weighted under 2,500 g and preterm delivery in cleft lip and/or palate subjects was significantly higher than that of control subjects.
6. Associated malformations: percentage of associated malformations with cleft including still-birth was 21.3%, and highest in cleft palate alone. Malformations most commonly associated were abnormalities of limbs, micrognathia, heart malformations and anecephalus.
