A Dose of Prevention

The interplay of cells and tissues that marks the growth of an embryo is one of nature's most exquisitely orchestrated movements. And, for vertebrates, the formation of the spinal cord and brain from a simple tube of cells is as crucial to life as it is beautiful to contemplate. But any defect in this neural tube, likely to appear early in development, can be devastating. Among the possible results: anencephaly, in which a baby is born minus most of its brain, and spina bifida.

In the latest issue of the New England Journal of Medicine, a team of researchers from Hungary report that women who consume 0.8 mg of folic acid, a B vitamin, for at least a month before they conceive have a dramatically lower risk of bearing a child with a neural-tube defect. Although the link between folic acid and neural-tube defects has been made before, this landmark study of 4,156 women is the first to show that the malformation can be prevented -- even in women who have no previous history of bearing children with neural- tube defects.