MONDAY, Dec. 31 (HealthDay News) -- When Americans hear "cleft lip" or "cleft palate," they often think of children in developing countries, but U.S. babies are by no means immune to the birth defect.

Each year about 7,000 American children are born with an oral cleft defect, according to the U.S. Centers for Disease Control and Prevention. This means that their lip hasn't formed completely and isn't closed properly in the case of cleft lip or, in the case of cleft palate, that there's a hole in the roof of their mouth.

The good news, though, is that the condition is treatable.

"The outcomes for children are excellent," said Dr. Joseph Shin, chief of the division of plastic and reconstructive surgery at Montefiore Medical Center in New York City. "Children do fine with it. It's not the end of the world." Shin has served on humanitarian surgical missions for Operation Smile and other organizations to repair cleft lips and cleft palates in countries in South America, Mexico, Morocco and the Middle East.

Cleft lip and cleft palate aren't just cosmetic concerns, however. "There's a lot of function in the palate and the lip," explained Dr. Laura Swibel Rosenthal, an assistant professor in the departments of otolaryngology and pediatrics at Loyola University's Stritch School of Medicine in Chicago. "Babies have to eat and not have food go up through their nose."

Children born with these conditions can also have problems with their ears and sinuses because fluids can travel where they shouldn't. If the defects are not corrected when children are young, they can also interfere with a child's ability to speak properly. And, when the cleft is in the front of the mouth, it interferes with the development of the teeth, said Swibel Rosenthal, who added that sometimes, surgery is needed to move the jaw forward.

It's not clear exactly what causes oral clefts, according to the March of Dimes. Some factors that have been associated with an increased risk for cleft lip and palate include changes in some genes, a deficiency of folic acid before pregnancy, taking certain medications while pregnant, drinking alcohol during pregnancy and having certain infections during pregnancy.

But the biggest risk factor linked to oral clefts is smoking during pregnancy. About one in five babies born with a cleft lip or palate is born to a mother who smoked, according to the March of Dimes.

Shin noted, however, that "sometimes you can do everything right, and you can still have a child with cleft lip or palate."

For babies born with a cleft lip or palate, surgery is the main treatment. For cleft lip, he said, surgery is generally scheduled when the child is about 3 months old. For a cleft palate, surgery is usually done at about 1 year old or slightly younger so that there are fewer issues with speech, he said.

"The sooner you can do the repair, the better babies heal," Shin said.

Besides the procedures to repair the cleft lip or palate, children often also need surgeries for ear tubes to keep their ears clear of fluids while the repair is healing. Depending on the severity of the cleft palate and how the initial surgery has healed, children sometimes need a second surgery on their palates when they're 3 to 7 years old, according to Swibel Rosenthal. Also, cleft lips sometimes require a second surgery to get a better cosmetic outcome, she said. Most kids also will need braces, she added.

"Parents shouldn't be nervous about these conditions," Swibel Rosenthal said. "Although they sometimes require multiple surgeries, there are ways to treat cleft lip and cleft palate that are simple, and children do very well."

Because cleft lip and palate can be genetic conditions, it's possible that subsequent pregnancies may result in another baby being born with cleft lip or palate, though the odds are relatively low, she said. "If there's only one family member affected, the chances of another child having an oral cleft are about 4 percent," she noted. "If two or more family members are affected, the chances of another child having it are about 9 percent."

More information

The March of Dimes Foundation has more about cleft lip and palate.

To learn how one family dealt with an oral birth defect, read here.