Neural tube defects are among the most common major congenital anomalies in the United States and are associated with significant disability and death.  The risk of neural tube defects can be prevented with daily folic acid supplementation in the periconceptional period.  However, most women do not receive the recommended daily intake of folate.  January 5–11 is national Folic Acid Awareness Week, a time when we remind all women of childbearing age about the important taking folic acid during pregnancy.

The US Preventive Services Task Force (USPSTF) last issued recommendations on folic acid supplementation in women of childbearing age in 2009.  In 2009 and in an updated report published in JAMA last week, the USPSTF unequivocally recommends that ALL WOMEN who are either planning or capable of pregnancy take a DAILY SUPPLEMENT containing 0.4 TO 0.8 mg (400-800 µg) OF FOLIC ACID.  

Folic acid is found in dark green leafy vegetables, legumes, oranges, and fortified cereal grains; however, the National Health and Nutrition Examination Survey (NHANES) data from 2003 to 2006 suggest that 75% of nonpregnant women aged 15 to 44 years do not consume the recommended daily intake of folic acid for preventing neural tube defects.

Half of all pregnancies in the United States are unplanned.  Therefore, clinicians must advise all women who are capable of pregnancy to take daily folic acid supplements. The critical period for supplementation starts at least 1 month before conception and continues through the first 2 to 3 months of pregnancy.

While the USPSTF focuses primarily on risk for neural tube defects, other studies indicate that periconceptual use of folic acid reduces risk for other congenital malformations, including oral clefts.  In addition, folic acid supplementation has been associated with clinically significant reductions in risk of miscarriage, stillbirth, preterm birth, and neonatal mortality.

When we meet with women regarding the use of psychotropic medications during pregnancy, we spend most of our time discussing the potential risks of exposure to medications.  However, looking at these data, probably one of the more impactful things we can do during these consultations is emphasize the importance of periconceptual use of folic acid.  It has been my experience that many women do not know exactly why they are supposed to take prenatal vitamins and may erroneously assume that the vitamins are recommended to offset any nutritional deficiencies they encounter ast a result of morning sickness.  In addition, any women also start their prenatal vitamins after the pregnancy is documented, which is too late to modulate risk for neural tube defects.   

Ruta Nonacs, MD PhD