Cleft lip is a treatable birth defect that appears as one or more splits (clefts) in the upper lip. Cleft lip can range from a small indentation in the lip (incomplete cleft) to a split in the lip that may extend up into one or both nostrils (complete cleft), and sometimes into the palate.

Cleft lip often occurs with cleft palate. These conditions are the most common birth defects of the head and neck.

Cleft lip forms early in pregnancy. The main causes seem to be family history and health issues during pregnancy.

This condition can be corrected with surgery, usually within the first few months of life. Depending on the type and severity of the cleft, more than one surgery may be needed. Sometimes other treatments, such as speech therapy, are also helpful.