Cleft lip and cleft palate are considered to be two separate birth defects. Cleft lip happens to one in every one thousand births and is more common than cleft palate. Cleft palate occurs in one in every two thousand births. Both cleft lip and cleft palate occur more often in Asians and certain groups of American Indians. Boys are more susceptible to cleft lip and girls to cleft palate. Even though they are considered two separate birth defects, a baby can be born with both.

A cleft is defined as a separation in a body structure. Cleft lip and palate both occur in the early stages of pregnancy. At about five weeks into pregnancy the tissues of the upper jaw and nose don't join as they are expected to. Cleft palate is when the roof of the mouth does not develop normally and fuses together. This would occur in about the tenth week of pregnancy.

It is not known on how cleft lip or palate happens. There have been genetic links to both. If you have a cleft lip or palate chances are that you could pass that on to your own kids. However if parents do not have either form of cleft and have a baby with a cleft the chances of having another baby with a cleft is around 2-8 percent. If another baby is born with a cleft it will be the same as its sibling. If a parent has a type of cleft, then their children have an increased risk in about 4-6 percent, however the more children you have the higher the risk. Research has shown that cigarette smoking during pregnancy greatly increases the risk of both. There are a few genes as well as environmental factors that could contribute to these birth defects. Drinking during pregnancy and a deficiency of folic acid have both been linked to an increased risk in developing cleft lip or palate, as has the mother having an illness during pregnancy. Babies born with cleft lip have a 13% chance of having other birth defects. Cleft palate is known to be associated with more genetic syndromes than cleft lip. Research has shown that babies that are born with a cleft palate are at 50% risk in having other birth defects.

Surgery for cleft lip is usually done in the first five months or earlier. It depends on the severity of the cleft. Some doctors may prefer to correct the cleft when the baby is healthy, weighing at least ten pounds and is ten weeks old. Before the surgery on the cleft the baby may be fitted with a piece to support their lip during feeding. Corrections for a cleft palate are different. The ages for surgery are usually around nine to eighteen months. Additional surgeries may be done if the shape of the baby's nose is irregular, for cosmetic reasons. Other treatments may be offered if any other problems come up, such as speech therapy.