Descriptive epidemiology of orofacial clefts in South Australia.

Objective: There is wide variability in the prevalence of orofacial clefts at birth across geographic locations. The study aimed to quantify the prevalence of orofacial clefts and provide demographic details of the individuals identified with an orofacial cleft in South Australia.

Methods: The South Australian Birth Defects Register (SABDR) data was used to identify individuals born in South Australia with any orofacial cleft including cleft lip (CL), cleft lip and palate (CL + P), cleft palate (CP), cleft uvula (CU) and facial clefts (FC) between 1986 and 2019. The proportion of orofacial clefts for livebirths was calculated by sex, Indigenous status, geographic location, socioeconomic status, maternal age, plurality, gestation, birthweight and family history of orofacial clefts.

Results: A total of 1127 individuals were identified as having an orofacial cleft and livebirth: with a combined prevalence of 17.1 in 10,000 or 1 in 580 livebirths for all orofacial clefts. The prevalence for CL was 3.3 per 10,000, CL + P was 5.4 per 10,000, CP was 8.1 per 10,000, CU was 0.2 per 10,000 and FC was 0.1 in 10,000. A greater proportion of orofacial cleft diagnoses were male, born in major cities, non-Indigenous, higher SES, lower maternal age, normal gestational age and birthweight, non-syndromic diagnoses, with no family history of orofacial clefts.

Conclusions: Prevalence data provides an understanding of individuals born with orofacial clefts in South Australia since 1986 which are comparative to national and international birth registries. The quality of the SABDR is high and provides a reference for comparison to published prevalence reports.