Epidemiology of cleft lip and palate in Thailand.

During the years 1989 to 1991, a survey for the epidemiology of cleft lip and palate was carried out in Thailand using detailed forms. One thousand ninety-six patients were recorded and 593 patients were operated during that period. All records were analyzed. Six hundred forty-seven patients (59%) lived in northeastern Thailand. Of the 593 operated patients, 26% had cleft lip only, 48% had cleft lip and palate, and 25% had cleft palate only. Men predominated all groups except for the cleft palate-only group. Twenty-six of 593 patients had associated congenital anomalies. Two hundred thirty-seven of 1,096 patients had a history of cleft lip and palate in their first- and second-degree relatives (21.62%). Five hundred seventy-eight of 1,096 mothers (52.74%) had a history of taking drugs. Analgesics were among the drugs taken most often.