Diagnosis and Management of Neural-Tube Defects Today

About 10 of every 10,000 American babies are born with anencephaly or meningomyelocele (spina bifida), the disorders known collectively as neural-tube defects. The incidence of anencephaly has declined from 8 per 10,000 live births in 1970 to about 3 to 4 per 10,000 in the 1980s. Similarly, the incidence of meningomyelocele declined steadily from 12 per 10,000 in 1970 to 6 to 8 per 10,000 in 1980, where it has plateaued since.1 The neural tube closes between 22 and 29 days after conception; disruption of the events that are programmed to occur during this critical period of development results in . . .