Incidence of Cleft Lip and Palate and Risks of Additional Malformations

Abstract

Children with cleft lip and/or palate (n = 251) born between 1991 and 1995 in the county of Stockholm, Sweden, were studied with reference to incidence and rate ratios (RRs) of different types of clefts, gender, birth weight, mother's age, and length of pregnancy. Children who had clefts and additional malformations were compared with children who had clefts but no additional malformations. The incidence of clefts was 2.0/1000 live births, and it was higher among males than among females. The RR, an index of relative risk, was 1.58. The main groups, children with isolated cleft lip, children with cleft lip and palate, and children with isolated cleft palate, showed similar incidence values (0.6-0.7/1000 live births). Children with bilateral clefts had an incidence of 0.3/1000 live births. Additional malformations were found in approximately every sixth newborn with a cleft when children with Robin sequence were excluded. There was a tendency for newborns with bilateral clefts to have additional malformations (RR = 1.36; confidence interval = 0.74-2.49). Children with clefts and additional malformations had lower birth weight and were born earlier than children with clefts only. Preterm cleft children with low birth weight should be screened for the presence of other birth defects.