Incidence of cleft lip and cleft palate in 39,696 Japanese babies born during 1983.

To estimate the incidence of cleft lip and/or cleft palate among the Japanese, 39,696 Japanese babies born during the period from January 1, 1983 to December 31, 1983, were investigated. It was found that 65 babies (0.163%) had these abnormalities, and that the ratio of the birth of such babies was approximately one per 611 in the population. Of the 65 affected babies, 41.3% presented cleft lip (CL), 46.0% cleft lip and palate (CL/P), and 12.7% cleft palate (CP). These results suggest that the incidence of CL/P in the Japanese is higher than that observed among other races.