National Folic Acid Awareness Week occurs from January 7 to 13 this year, highlighting the importance of folic acid for reproductive aged women.
We care about folic acid because of its association with neural tube defects (or NTD). NTDs are congenital abnormalities that affect the central nervous system and vertebrae. Out of all major congenital anomalies, NTDs are the second most commonly diagnosed. These defects can range from small and surgically correctible (such as some cases of spina bifida) to being incompatible with life (such as anencephaly).
Folic acid became a target of concern when it was noticed more than 40 years ago that levels of this B vitamin were much lower in women who had a pregnancy complicated by an NTD. Studies were then done in women who had had a pregnancy with a NTD that included folic acid supplementation; those women who received the supplement had a 72% protective effect against having another pregnancy complicated by NTDs.
Given this encouraging data, the effect of folic acid supplementation in unaffected women was investigated, and again results showed that receiving this vitamin decreased the chances of having a pregnancy complicated by NTDs.
Because of these studies, it is now recommended that all women who plan to become pregnant should take 400 micrograms of folic acid daily, and those women who are higher risk (such as those who have a seizure disorder or who have had a pregnancy complicated by an NTD) should increase that dose to 4 mg a day.
The fortification of wheat flour in the United States with folic acid is an example of taking a public health approach to disease prevention. Based on the strong data that folic acid supplementation decreases NTD risk, and understanding that not all women will appropriately supplement, in 1998 this vitamin was added to wheat flour. This means that foods commonly consumed such as cereals, enriched flours, rice, and pasta were now fortified with folic acid. This initiative alone has been attributed with a 19 percent decrease in NTD incidence in the United States!
We don’t completely understand why exactly folic acid is so important in NTD prevention. It is possible that some reactions involved in cell growth depend on folate, and the lack of folate interrupts certain important parts of neural tube formation and closure.
Supplementing with adequate folic acid will not prevent all NTDs, however, but it is estimated that it will prevent between 16 and 58 percent of NTDs. The remaining cases are likely due to multifactorial etiologies such as genetic predisposition, obesity, and exposures to certain medications, environmental exposures, and maternal medical conditions.
The problem with neural tube formation – and why it is so important for all women of childbearing age to be receiving adequate folic acid supplementation – is that it occurs just 3 to 4 weeks after fertilization. Unfortunately, this is often before many women realize they are pregnant. If they wait until after this time to start taking a prenatal vitamin (which contains folic acid), then they will have missed the window when folic acid would be beneficial. And given that half of all pregnancies are unplanned, it is insufficient to only discuss this with women who are actively trying to conceive since that will leave many women inadequately prepared.
This is why anyone who routinely cares for women who are capable of becoming pregnant should screen for and recommend the initiation of folic acid supplementation if they are not already supplementing or consuming adequate folic acid via fortified foods. This is not just an OB/GYN issue, but should be on the minds of all primary care doctors who care for these women.
If you are looking for a comprehensive pregnancy solution, The Wellness Network offers clinically-accurate patient education that helps you connect with expecting and new moms from pregnancy to early childhood. Additionally, The Wellness Network’s pregnancy and parenting site Bundoo, provides evidence-based articles authored by healthcare professionals available for licensing for use on your website or to embed on your facility‘s app. Additional recommended resources include this infographic from the CDC, and the American College of Obstetricians and Gynecologists Frequently Asked Questions regarding birth defect prevention.
- The American College of Obstetricians and Gynecologists. Practice Bulletin #187: Neural tube defects. December 2017.
- The Centers for Disease Control. Folic Acid.