Orofacial clefts are openings in the lip or roof of the mouth that result from arrested embryonic development in the first trimester. They are among the most common congenital malformations, with an incidence of 1 to 2 per 1000 live births (Derijcke et al., 1996). Presentations include cleft lip only (CLO), cleft palate only (CPO) and cleft lip and palate (CLP). Clefts can also be categorized as ‘unilateral’ or ‘bilateral’ (involving one or both sides of the lip and/or palate), and ‘incomplete’ or ‘complete’ (involving only the soft palate versus both the soft and hard palates, and/or involving only the lip versus the lip and gumline). Most clefts are ‘nonsyndromic’, meaning that they are not associated with other malformations. Although aetiology remains unclear, most cases are believed to result from a combination of genetic vulnerability and prenatal exposures (e.g. tobacco, anticonvulsant medications), possibly interacting with maternal nutritional status (Prescott & Malcolm, 2002).

Clefts of the lip and palate can be detected by ultrasound in utero. Though this technology is developing rapidly, many cases are missed and often the diagnosis is not made until birth (see ‘Screening: antenatal’ and ‘Foetal wellbeing’). During the neonatal period, most families are referred to a specialty hospital-based clinic for management of their child's care. Surgical repair of the cleft lip is typically undertaken by age 5 months, followed by cleft palate repair when children are 12–18 months old. Subsequent procedures and surgical revisions are scheduled according to patients' needs (see ‘Reconstructive and cosmetic surgery’).