Abstract

Neural tube defects (NTDs) are unwanted congenital expressions associated with a folic acid deficiency in pregnant mothers. In the United States, 1–2 per 1000 children are born each year with disruptive anomalies due to neural tube defects. Augmenting the diet with folic acid (vitamin B9) supplementation by the maternal parent before conception and during the first trimester of pregnancy reduces the risk of NTDs in children. Folic acid and folate cannot be synthesized in sufficient amounts by the body and must be obtained from the diet or supplementation. Many women have sub-optimal levels of folic acid, which is essential for nucleic acid synthesis. Folic acid supplementation in pregnancy dates to the 1930s and 1940s. Currently, folic acid is recommended and prescribed for pregnant women and during preconception. However, an excess amount of folic acid can have adverse effects on the mother and fetus. Thus, an optimal folic acid prescribed dosage should be further investigated. Some studies have demonstrated that the current standard of folic acid supplementation could be more than what an individual woman’s body needs and can utilize, and excessive folic acid supplementation could prove harmful. A woman’s existing folic acid levels are rarely evaluated before recommending the standard, “one-size-fits-all” recommendation. Thus, it would be more effective (and potentially less harmful) to determine a woman’s folic acid level, and to prescribe an optimal dose customized for the individual. The following review provides 1) a historical backdrop to neural tube defects and folic acid, 2) describes the current folic acid supplementation protocol, and 3) suggests a more effective and potentially less harmful folic acid screening and supplementation regime. Continuing research and refining folic acid supplementation in periconception is worthwhile and fundamental as there are high financial and emotional costs associated with folic acid-related NTDs.

Keywords: Anaemia; Birth Defects; Folate; Folic Acid; Neural Tube Defects; Periconception; Pregnancy

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