What causes a cleft lip and palate?

Unilateral & Bilateral Cleft Lip and Palate

During the early stages of pregnancy, the upper lip and palate develop from tissues lying on either side of the tongue. Normally, as the face and skull are formed, these tissues grow towards each other and join up in the middle.

When the tissues that form the upper lip fail to join up in the middle of the face, a gap occurs in the lip. Usually, a single gap occurs below one or other nostril (unilateral cleft lip). Sometimes there are two gaps in the upper lip, each below a nostril (bilateral cleft lip). When the palate fails to join up, a gap is left in the roof of the mouth up into the nose.

We don't know why the 'joining up' process fails in this way. Some evidence suggests there may be a genetic factor, as cleft lip and palate can run in families.

It is thought, however, that certain types of drugs may increase the risk. (Please see Prevention, below).

Feeding

The most immediate problem caused by a cleft lip or palate is likely to be difficulty with feeding. Many babies with a cleft lip can breastfeed. However, some have difficulty in forming a vacuum in order to suck properly. Babies with these problems may need a special teat and bottle that allow milk to be delivered to the back of the throat where it can be swallowed. Sometimes, special dental plates can be used to seal the roof of the mouth to help the baby suckle milk better.

Babies who find it difficult to feed may gain weight slowly at first, but have usually caught up by the time they are six months old.

Speech and hearing

Cleft palate can cause problems with speech. The size of the cleft is not an indicator of how serious such problems are likely to be - even a small cleft can affect speech quite seriously. Most children go on to speak normally after the palate is repaired, although some may develop problems such as nasal speech.

Hearing may be affected because the muscles of the palate affect the ear, making the child more likely to develop "glue ear". This is a condition where thick sticky fluid accumulates behind the eardrum as a result of an infection of the middle ear. Doctors call it otitis media with effusion. It can cause temporary hearing loss but can be treated with antibiotics or, if it is an ongoing problem, with a minor operation to insert a tiny plastic tube (a grommet) into the eardrum through which the fluid can drain.

Occasionally, cleft palate may also affect the growth of the jaw and the development of the teeth.

Ideally, children with cleft lip and palate are treated by a specialist "cleft team" that includes plastic, maxillofacial and ENT surgeons as well as speech and language therapists, dentists, orthodontists, psychologists and specialist nurses. Care and support of the child and the family should last from birth until the child stops growing at about age 18.

There are about 10 specialist centres in the UK that have established this type of "multidisciplinary" team and experts agree that the surgery and subsequent care should be undertaken by professionals who routinely work in this field. If you have a baby born with a cleft lip or palate, your maternity hospital should refer you to such a specialist centre.

Surgery

How a Cleft Lip Can Be Repaired

Surgery is the most common treatment for cleft lip and palate. The type of operation required depends on the severity of the cleft. Often a number of operations are performed as the child grows.

Surgery to close the gap in the lip is usually first performed three months after the baby is born. Surgery to close the gap in the palate is usually done at about six months old. Both operations are done with the baby asleep under general anaesthetic and involve a hospital stay of three to five days.

As the child grows older further surgery may be needed to improve the appearance of the lip and nose and the function of the palate. If there is a gap in the gum, a bone graft may be used to fill it.

Other treatments and therapies

Speech and language therapy may be used to monitor and develop speech. Orthodontic treatment (braces, for example) may be used to ensure that the permanent teeth come through straight and in the right place.

Support is essential both for new parents coming to terms with their child's special needs, and for the children themselves who may have to deal with teasing at school and the difficulty of being different. It can help to discuss the problems with people who have had similar experiences or by having access to psychological support available from specialist cleft teams.

With so little known about the cause of cleft lip and palate, even less is known about prevention. The most sensible approach is simply to do everything possible to ensure a healthy pregnancy, avoiding known dangers such as alcohol and smoking. Some people believe that taking a supplement of folic acid around conception and in early pregnancy can help prevent cleft lip and palate. There is little evidence to prove this, although research has shown that folic acid can reduce the risk of neural tube defects such as spina bifida.

It is thought that certain types of drugs may increase the risk of cleft lip and palate.

These include:

Anticonvulsives, which are usually used to treat conditions such as epilepsy that involve seizures. Examples include phenytoin and sodium valproate.

Benzodiazepines such as diazepam, which may be used to treat insomnia and anxiety (although their use long- term is now discouraged because of their potential to cause dependence).

Corticosteroids, which are used for a wide variety of conditions. Evidence suggests that the risk of cleft lip and palate is associated with the use of high-dose oral corticosteroids during early pregnancy. However, in some cases the benefits of corticosteroids (eg to help reduce the risk of premature birth) may outweigh the risk of cleft lip and palate.

Cleft Lip and Palate Association (CLAPA)
Voluntary organisation supporting people affected by cleft lip and palate.
020 7431 0033
www.clapa.com