Cleft lip and palate (prenatal)

Definition

• The clefts develop during weeks 6 to 8; the primary and secondary palate have different embryological origins.

Classification

• Cleft lip with or without cleft palate is distinguished from isolated cleft palate; the spectrum ranges from bifid uvula as the mildest form through clefts of the soft palate only to complete clefts of the soft and hard palate, alveolar process and lip.
• About 30% of clefts are syndromic and about 70% non-syndromic (isolated).

Occurrence & epidemiology

Epidemiology

• Together, cleft lip and palate are the most common congenital anomalies of the head and neck, with a total prevalence of about 1 in 600 to 1,000 live births; they are most frequent in people of Asian and Native American origin.

Aetiopathogenesis

Aetiology and risk factors

• Genetic and environmental factors are involved; syndromic clefts are typically caused by chromosomal abnormalities or defined monogenic syndromes.
• Risk factors include smoking and alcohol use in pregnancy, a cleft in the mother or a first-degree relative and possibly folate deficiency, including from folate antagonists such as phenytoin, valproate or carbamazepine.

Clinical features

• Clefts impair feeding through nasal reflux, an inadequate latch and increased work of feeding with fatigue; later, speech development is impaired and middle ear infections are more frequent.

Diagnosis

• Prenatally, clefts are sought with 2D ultrasound; supplementary 3D ultrasound or MRI improves diagnostic accuracy in most studies.
• After birth, besides clinical examination, genetic evaluation is undertaken even for apparently isolated clefts, for example with chromosomal microarray analysis or gene panels.

Keep learning in the app

Further reading (selection)

1. StatPearls: Cleft Palate (NCBI Bookshelf)
2. MSD Manual Professional Edition: Cleft Lip and Cleft Palate
3. J Clin Med 2024: Diagnostic Methods for the Prenatal Detection of Cleft Lip and Palate – systematic review (PMC, open access)

Cross-references