Oral Birth Defects
Oral clefts most commonly occur in the lip and/or palate. These facial and oral malformations occur within the first six to eight weeks of pregnancy. The formation of the head and facial development of the fetus depends upon a complex series of developmental events, normally leading to the fusion of the embryonic facial lobes. The process, however, is extremely susceptible to environmental and genetic factors. When the tissue in the mouth and lip area fails to grow together, a gap, or cleft, results where the tissues should have fused. This can happen in any single site where the lobes would ordinarily come together or simultaneously in several or all of the sites. The resulting malformation reflects the locations and severity of individual fusion failures, and can range from a minor lip or palate fissure to a severe facial deformity.
The Effects of Oral Clefts
Because of the numerous potential problems that may result from these birth defects over time, including difficulties with feeding, ear infections, speech, and socialization, it is important that clefts be surgically repaired when the child is very young.
Feeding problems occur because the cleft does not allow normal suction. An infant with a cleft palate must be fed in an upright position so that gravity helps prevent milk from coming through the baby’s nose. Specially designed bottles can sometimes help.
Children with cleft are extremely susceptible to middle ear infections, which can eventually cause hearing loss. The infections occur when the Eustachian tubes and external ear canals are angled in such a way as to lead to contamination from food, whereas the ears are normally self-cleaning. Because proper hearing is a necessary prerequisite to speech, babies with hearing loss related to cleft palate will not try to mimic the sounds of speech, and because the lips and palate are used in pronunciation, children with cleft will often require extensive speech therapy.
Furthermore, because a cleft lip or cleft palate may affect a child’s self concept, it can cause issues with self-esteem, social interaction, and behavior.
The FDA Links Topamax with an Increased Risk of Oral Clefts
The U.S. Food and Drug Administration has issued new stronger warnings regarding the use of topiramate, an epilepsy drug that is also prescribed to prevent migraines, because new data indicated an increased risk of birth defects, notably oral clefts, when the drug is taken in early pregnancy.
Topirimate is sold by pharmaceutical giant Johnson & Johnson under the brand name Topamax. Generic versions are also available. The FDA reviewed pregnancy databases from the North American Antiepileptic Drug Pregnancy Registry, which revealed that cleft lip and cleft palate occurred in 1.4% of babies exposed to topiramate alone in early pregnancy, compared to a rate of 0.38% to 0.55% in infants exposed to other anti-epileptic drugs, and 0.07% in infants of women with no exposure to anti-seizure medications. The damage occurs in the first trimester when a woman may not realize that she is pregnant, making it important that women of childbearing age be warned of the possible hazards, and that alternative medications carrying less risk of birth defects be considered. In addition to treating epilepsy and preventing migraines, topirimate is sometimes used off-label to treat other conditions, such as obesity, bipolar disorder, and alcoholism.
Topirimate has been reclassified for use in pregnancy as a Category D drug, which means there is evidence of risk to the fetus, but in some situations, the benefits may still outweigh the risks. The FDA had previously given the drug a Category C designation because of a lack of human data.
