About 1 in 750 babies in the United States is born with a cleft lip and/or palate. A new study now finds that women who take folic acid in the periconceptional period can substantially reduce the risk of cleft lip and palate in their offspring.1 The study, conducted by the National Institute of Environmental Health Sciences, found that 0.4 mg (400 mcg) of folic acid daily reduces the risk of cleft lip (with or without cleft palate) in the fetus by one-third. There was no apparent effect on the risk of cleft palate alone. The lowest risk of cleft lip was among women with folate-rich diets who also took folic acid supplements and multivitamins. Facial structures that form the embryonic lip fuse during the fifth and sixth weeks of life, about 8 weeks after the last menstrual period, whereas the palatal shelves fuse during weeks 7 to 10. Folic acid supplementation is already known to reduce the risk of neural tube defects, such as spina bifida.

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