A cleft palate with a unilateral cleft lip is a common birth defect in which a baby's lip and palate (roof of mouth) don't form properly. As a result, there is a split or opening (cleft) on one side of the lip that can extend all the way from the nose to the back of the palate.

More to Know

Cleft lip and cleft palate are called orofacial clefts. Because the lips and the palate develop separately, a child can be born with a cleft lip only, cleft palate only, or both.

Sometimes a cleft occurs as part of a syndrome, meaning there are other birth defects. Other times, it's genetic and runs in families. A cleft also can be associated with environmental factors, such as a woman's use of certain medications, exposure to cigarette smoke, or lack of certain vitamins while pregnant. Most of the time, though, the cause isn't known.

Cleft lip and cleft palate can be associated with other problems, including feeding difficulties, fluid buildup in the middle ear and hearing loss, dental abnormalities, and speech difficulties.

Keep in Mind

The good news is that cleft palate with unilateral cleft lip is treatable. Most babies born with orofacial clefts can have surgery to repair the defect within their first year, and will go on to lead normal, healthy lives. They may, however, need to have additional surgeries as they grow older.

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