, also known as congenital double lip, is a rare birth defect which affects the upper lip more often than the lower lip. It consists of a fold of excess tissue on the interior of the lip. It is most visible when the person smiles, talks or shows their teeth. Although the extra tissue may interfere when the person is speaking or chewing, surgery to remove the extra tissue is usually done for cosmetic reasons (to improve appearance). The double lip may not be that noticeable at birth but often becomes more obvious as the person grows. It is generally accepted that double lip does not depend on race or gender, however in a recent report in 2009, it has been suggested that males were 7 times more likely to have double lip than females. Double lip may occur alone or as part of Ascher's syndrome (for more information, visit Ascher’s syndrome.
) It is not known how often babies are born with double lip.