Cleft lip is an opening or gap in the lip which occurs as a congenital deformity caused by inability of facial structures to fuse together during gestation period. There is a possibility of this deformity to affect other parts of the face like eyes, ears, nose, cheeks and the forehead. Several factors are implicated in the cause of this deformity. These factors include genetic, syndrome, non-syndrome as well as environmental factors. There are also researches currently going on to ascertain the possibility of other causes of this deformity.

Genetic causes of this condition are still not explicit but there are serious indications that genes may be involved. Most syndromes like Van der Woude Syndrome and Stickler’s syndrome have been implicated as a cause of this deformity. Some genes that are connected to some syndromes have also been recognized as contributors to cases of cleft lip. Environmental influences or substances that may have a gene mutation effect can also be responsible for clefting of lip during intra-uterine life. Substances investigated for this include: maternal diet, environmental pollutants, illegal drugs (cocaine, heroin etc) and alcohol.

Cleft lip can easily be treated through surgery. To get the best results, this is normally done between 2-3 months after delivery or during early childhood.