[Epidemiological investigation of cleft lip and/or palate. II. Incidence of cleft lip and palate among Japanese babies in Gifu prefecture 1986 to 1987].

Since 1981 we have been conducting investigations in Aichi Prefecture where our institution is located in close cooperation with Medical Association of Obstetrics-Gynecologists and member physicians of the Midwives Association. In addition, we surveyed 111 institutions in Gifu Prefecture for the patient who was delivered from January 1, 1986 to December 31, 1987 to learn the incidence and type classification of cleft lip and/or palate in the general population Gifu. Consequently, we acquired the date of 20667 newborns. It was found as a result that 35 babies had these abnormalities and that ratio of the birth of such newborns was one for 590.5 deliveries. Among 35 cleft infants 12 (34.3%) with cleft lip and palate, 5 (14.3%) cleft palate. Looking at the estimates from the results of our investigation, the annual number of newborns with these disease in the Gifu Prefecture was 41.6 to 41.9 in 1986, 33.5 to 33.6 in 1987 with 95 percent confidence limits.