RESUMO
OBJECTIVE: The purpose of this article is to determine the prevalence of the cleft lip and palate and its association with some risking factors. MATERIAL AND METHODS: A retrospective, observational and analytic study, of 44 newborn infants with cleft lip and palate and their controls, in 33,461 consecutive births, with 20 weeks or more, and birth weight more than 500 g, since November of 1988 to June of 1991. The information were obtained from the database of the Congenital External Malformation Register, done by the University of Guadalajara, in four hospitals. The prevalence of the cleft lip and palate was calculated. Of the variables studied their association was searched with congenital malformation in 2 x 2 tables, calculating, its chi square, confidence interval, and old ratio. RESULTS: The prevalence of the cleft lip and palate was of 13.2 x 10,000 births. By categories: cleft lip 2.7 x 10,000, cleft lip and palate 7.8 x 10,000 and cleft palate 2.7 x 10,000. The only statistics differences with control group were the association with antecedent of other malformation in the family and methrorrague during pregnancy. CONCLUSIONS: The found prevalence is similar to the one informed in the literature, with some differences by categories. The association with antecedent of another malformation in the family, support the role of the hereditary role in the multifactorial etiology.