Cleft lip occurs when the tissue of the upper jaw and nose does not blend perfectly, resulting in a cleft or a gap. This gap can occur only on the lips (cleft lip), roof of the mouth or palate (cleft palate), or even both. During pregnancy between the fifth and ninth week, the face and jaw develop. At this time in normal infants, parts of the face and jaw are well integrated, but this unification is disrupted in babies born with cleft lip conditions. Cleft lip is divided into two types, namely unilateral cleft and bilateral cleft. Unilateral cleft occur only on one side of the lip while bilateral cleft occurs on two sides of the lip. Cleft Lip Symptoms Cleft lip is usually known when a newborn baby. The main sign is cleavage on the lips. The shape can be a small gap in the lips or a longer gap. This longer gap extends from the lips to the upper gums, palate and nose. There is also a cleft that occurs only in the soft palate muscles behind the mouth, but this condition is rare.