Cleft lip, jaw and/or palate is the most common type of facial deformity, and every year 150-200 children are born with this deformity in Sweden. Among infants with isolated cleft palate, it has not yet been established whether initial surgery at 6 months of age is more beneficial than at 12 months of age. For this reason, the researchers conducted a randomized trial in infants who did not have isolated cleft palate syndrome to investigate this further.

More than 500 infants at 23 centers in Europe and South America were randomized 1:1 to primary surgery either at 6 months (Group 1; 281 children) or at 12 months (Group 2; 277 children). Evaluations of video and audio recordings were performed at 1, 3, and 5 years of age by independent speech therapists who were unaware of the allocation between groups. The primary outcome was velopharyngeal insufficiency (poor palate function) at age 5 years, and secondary outcomes included speech development, postoperative complications, sound sensitivity, dental and facial development, and growth.

Speech recordings from 235 infants (83.6 percent) in Group 1 and 226 (81.6 percent) in Group 2 were analyzable. Pharyngeal hypofunction at 5 years was observed in 21 of 235 infants (8.9 percent) in group 1, compared with 34 of 226 (15.0 percent) in group 2 (relative risk, 0.59; 95 percent confidence interval, 0 , 36-0.99; P = 0.04). Postoperative complications were rare and did not differ significantly between groups. Four serious adverse events (three in group 1 and one in group 2) were reported but did not continue to follow-up.

A limitation of the study is that many infants were excluded because they were not considered medically suitable for surgery at 6 months of age or because of syndromes or developmental disorders that could affect the outcome.

Overall, the results suggest that infants who underwent primary surgery for isolated cleft palate at 6 months of age had a lower risk of developing hypopharyngeal insufficiency at 5 years than those who underwent surgery at 12 months of age. However, there may be reason to postpone surgical intervention, as many children are not medically ready for surgery after 6 months, and there is a lack of a perspective longer than 5 years in terms of clinically significant outcomes after surgery.