Chapter 2: How Do Clefts Occur

Facial and palate clefts are a persistence of the normal grooving or clefting of the face of the foetus. The developing face and palate are formed by the joining of separate component parts. Clefts of the lip are caused by the failure of the side or lateral component of the face to fuse with the middle or medial component. This causes disruption of both the lip and the jaw and front of the palate. The critical time for this fusion to occur is about the sixth week of pregnancy.

2.1 Normal formationof the lip and palate (H. Tuchmann-Duplesis and P. Haegel, Illustrated Human Embryology, vol.2, Springer Haegel, New York, 1982)

The palate fuses at a similar time. Prior to six weeks gestation, developing babies do not have a palate.

It is formed by palatal shelves that grow in from each side of the inner mouth. The joining occurs at approximately seven weeks in the middle of the mouth and proceeds zipper-like both backwards, forming the soft palate, and forwards, forming the hard palate. The process is completed by the twelfth week of pregnancy.

This means that all babies have a cleft face and cleft palate during the early development phase. Clefts are due to failure of closure of normal facial and oral structures at a critical period of development. Once the face and palate have formed, the palate cannot subsequently become clefted.

Further Information

To obtain further information on "Cleft Lip and Palate: A Parent's Guide", please contact Belinda Liston:

Jill Barbuto
Cleft Palate Clinic Coordinator
The Cleft Palate Clinic
The Children's Hospital at Westmead
Locked Bag 4001
WESTMEAD NSW 2145
AUSTRALIA
T: + 61 2 9845 2079
F: + 61 2 9845 2078
E: Jill.barbuto@health.nsw.gov.au