The epidemiology of orofacial clefts. 2. Associated malformations.

Using data from a French, the Swedish, and the California registries of congenital anomalies based on a total of more than 5 million births, the presence of nonfacial malformations in infants with cleft lip or cleft palate was studied. Cleft lip was less often associated with chromosome anomalies than cleft lip with cleft palate, but when all cleft lip/palate infants were compared with all infants with median cleft palate, chromosome anomalies were equally common. Ascertainment of chromosome anomalies in infants with facial clefts varied among programs. One hundred and twenty-one infants with non-chromosomal syndromes were identified-also, for these a marked variability between programs existed. An analysis of the type of associated malformations was made, comparing cleft lip/palate and median cleft palate infants. Some associations specific for the cleft types were described but to a large extent similar associations were found irrespective of cleft type. This may indicate that under certain circumstance, the various cleft types may have similar causes.