- The ARC - California Edition -

Progress in the Prevention of Neural Tube Defects

The January 1997 issue of Nature Medicine contains a report about research that indicates that a deficiency of a second B-vitamin, INOSITOL, is also involved in causing Neural Tube Defects (NTDS).

It is well over five years (August 1991) since the scientific community caused many people to sit up and take notice when they placed on the table evidence that NTDs can be significantly reduced in humans by having potential mothers consume the B- vitamin, FOLIC ACID. The timing of building up of the Folic Acid levels in the woman had to occur BEFORE conception and DURING the first trimester of the pregnancy.

The new research findings regarding Inositol, indicate that the Inositol may be capable of making a further reduction in the number of NTD cases. The research studied the effects of the Inositol vitamin on mice which had a genetic predisposition to birth defects similar to the spina bifida defect found in humans. The results of the research will require extensive follow up work in order to validate that the approach will consistently and safely work in the human system.

Neural tube disorders include anencephaly, spina bifida, and encephalocele and are the most common group of severe birth defects found in humans.

The term anencephaly is used to define a disorder where an infant is born with little or no brain. The skull does not close. Although about one-fourth of the anencephalic infants are liveborn, the majority die within hours or days of birth.

Spina bifida is a defect where the vertebral column fails to completely surround the spinal cord. The severity of spina bifida (open spine) depends upon the size and position of the defect on the spine, and whether or not it is covered by skin or membrane. About 85% of the infants with spina bifida have the most severe form, an uncovered or "open" defect. Twenty percent of those who survive to 5 years have moderate to severe mental retardation.

Encephalocele is a protrusion of the brain through a defect in the skull. The protruded brain is usually covered by a membranous sac. The impact on the infant depends on how much and what part of the brain protrudes.

Each year in the U.S. approximately 2,500 infants are born with a NTD (about 6 in every 10,000 live births). In addtion, an estimated 1,500 fetuses affected by these birth defects are annually aborted, according to the Centers for Disease Control (CDC).

Folic acid is also believed to be effective in preventing cleft lip and cleft palate. There are an estimated 7,000 cases annually of cleft lip and cleft palate nationwide. These birth defects often require several rounds of surgery during the infants’ first years of growth.

The California Birth Defects Monitoring Program has projected that 25% to 50% of cleft lip/palate will be prevented by the new Food and Drug Administration requirement to add folic acid into flour products.

Findings of researchers indicate that only 25% of NON-pregnant women regularly consume a vitamin supplement containing 0.4 mg folic acid, and only a small proportion eat a breakfast cereal containing 0.4 mg folic acid per serving.

(Adapted from The Arc of the US Q&A and other sources)