Cleft lip and palate are birth defects that occur because a baby’s lip or mouth does not form properly during pregnancy.

A cleft lip is an upper lip that is split. It is caused by the failure of the tissue of the lip to join before birth during the fourth through seventh week of pregnancy. The cause of orofacial clefts is usually unknown, however, the combination of genes and other risk factors, such as hormonal imbalances, nutritional deficiencies and certain medications taken during pregnancy may be causes.

A cleft palate occurs when the tissue that makes up the roof of the mouth does not join together during the sixth through ninth week of pregnancy. A baby may experience both the front and back of the palate being open or being open only in one area. A cleft palate is a more serious condition than a cleft lip, although both require surgery in order to be corrected.

Other risk factors that the CDC reports increase the chance to have a baby with an orofacial cleft are smoking, diabetes, and use of certain medications to treat epilepsy during the first trimester of pregnancy.

Oral issues that occur as a result of a cleft lip or palate can affect both baby and adult teeth including the positioning, size, shape, and number of teeth. Clefts can occur between the cuspid and lateral incisors.