Periodic Trends in the Incidence of Cleft Palate in a Cohort of Sri Lankan Cleft Palate Patients

Background: Over the last few decades the incidence of cleft palate has been increasing across the world. There are several genetic and environmental factors are reported to be among the causative agents of cleft palate. Theres scarcity of data with regards to the seasonality and the occurance of cleft palate among sri Lankans. Hence, the purpose of this study was to identify periodic changes in the incidence of cleft palate in a cohort of Sri Lankan population.Material & methods: Subjects (n=323) with cleft palate registered at the Regional Cleft Centre & Maxillo-Facial Department, Teaching Hospital, Karapitiya, Galle, from the 1st of January 2001 to 31st of December 2020 were included in the study. Structured interviewer based questionnaire was used to collect the information after obtaining the informed written consent.Results: Significantly higher number of cleft palate cases in this study were born in March (p = 0.008) compared with the national birth incidence while significantly lower numbers were born in October (p = 0.01). The sex ratio in the study sample was 0.71.Conclusions: The periodic trends in the incidence of cleft palate found in this preliminary study reinstated that environmental factors may have accounted for the reported seasonal variations observed in the incidence of cleft palate. Future studies are warranted to investigate the putative harmful seasonal factors that can influence the occurance of cleft palate.