Neural-Tube Defects

Each year spina bifida and anencephaly, the two most common forms of neural-tube defects, occur in 1 in 1000 pregnancies in the United States1 and an estimated 300,000 or more newborns worldwide.2 Although these severe conditions have been recognized since antiquity, never before has progress been so fast and substantive, particularly in the area of prevention. The results of randomized trials indicate that at least half the cases of neural-tube defects could be prevented if women consumed sufficient amounts of the B vitamin folic acid before conception and during early pregnancy.3,4 Elsewhere in this issue of the Journal, Berry . . .