This study (1) reviewed available data and recommendations regarding the prevention of neural tube defects (NTDs) through folic acid supplementation for the general population, women with previous NTD pregnancies, and women with epilepsy and (2) examined the potential role of pharmacy in the prevention of NTDs.
Methods
Published clinical literature was identified through a review of articles abstracted from MEDLINE and International Pharmaceutical Abstracts. Search terms were folic acid, neural tube defect, spina bifida, myelomeningocele, anencephaly, epilepsy, clinical guidelines, and pregnancy. Clinically relevant information consistent with current guidelines was extracted.
Results
Administration of 0.4 mg/day of folic acid to women of childbearing age decreases rates of NTDs. In the general population, two types of NTD-reduction strategies have been employed: educational campaigns and food supply supplementation. Continued surveillance of NTD rates is needed to fully assess the effect of food supply supplementation in the US. Women with previous NTD pregnancies should consume 4 mg/day of folic acid during the month before and the month after conception. Public health interventions, including targeted educational materials and a national database to track subsequent pregnancies in women with previous NTD pregnancies, are needed. No evidence-based information about the effectiveness or dosing of folic acid supplements in women with epilepsy is available.
Conclusions
Pharmacists have an important role to play in the education of other health care professionals and patients about periconceptual folic acid supplementation. However, pharmacists must first be prepared to fulfill this role. Significant research in special populations — to determine the best folic acid dose and the most effective educational strategies — should be undertaken in the future.
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