Folic acid is a nutrient found in green leafy vegetables and in some fruits and grains. Medical researchers have known for some time that that if pregnant women don't consume enough folic acid early in their pregnancy, it increases their babies' risk for neural tube defects such as spina bifida.
Now, new research performed by Allen Wilcox from the U.S. National Institute of Environmental Health Sciences confirms folic acid deficiency also contributes to the risk of cleft lip. "A cleft lip or what used to be called a hare lip, is a defect in which the upper lip and sometimes the upper bone of the mouth that form the upper teeth, does not form properly," he explains. "A cleft palate is when that defect occurs back further in the mouth, in the roof of the mouth."
Wilcox says the birth defects make it difficult for the baby to breast feed. "It also interferes with speech and infections in the ears, and there's all kinds of complications that can ensue," he adds.
The epidemiologist studied Norwegian babies born with cleft lip, cleft palate or both. He asked their mothers to recall whether they had taken pre-natal vitamins, or eaten diets high in folic acid and other folates. The usual amount of folic acid in prenatal vitamins is 400 micrograms.
"What we found was that the risk of cleft lip and cleft palate was reduced by about one-third among the women who reported that they were taking at least 400 micrograms of folic acid every day," he reports. Wilcox says women who took folic acid, but took less than 400 micrograms, "did not have any protection against cleft lip."
Wilcox says the effect of folic acid intake on the formation of cleft palates was not as strong. But he also says researchers think that defect has a slightly different cause than cleft lips.
Cleft lip and palate are two of the most common birth defects in the world. About two in every 1,000 babies are born with the problem.
Wilcox stresses that it's important for women to be taking folic acid if there's even the slightest chance of getting pregnant. "If women wait until they're pregnant to start taking vitamins, they may have already missed the early crucial stages of embryonic development where these birth defects are formed."
The research was published in a recent issue of the British Medical Journal.