Folic Acid supplementation and pregnancy: more than just neural tube defect prevention

Abstract

Folate (vitamin B(9)) is an essential nutrient that is required for DNA replication and as a substrate for a range of enzymatic reactions involved in amino acid synthesis and vitamin metabolism. Demands for folate increase during pregnancy because it is also required for growth and development of the fetus. Folate deficiency has been associated with abnormalities in both mothers (anemia, peripheral neuropathy) and fetuses (congenital abnormalities). This article reviews the metabolism of folic acid, the appropriate use of folic acid supplementation in pregnancy, and the potential benefits of folic acid, as well as the possible supplementation of l-methylfolate for the prevention of pregnancy-related complications other than neural tube defects.

Keywords: Dietary supplements; Folic acid; l-methylfolate.

Figure 1

Formation of l-methylfolate from folic acid. CH₂, methylene; CH₃, methyl group; DHF, dihydrofolate; DHFR, dihydrofolate reductase, F, folic acid; H, hydrogen; SHMT, serine hydroxy-methyl transferase; THF, tetrahydrofolate. Reproduced with permission from Stahl SM, Stahl’s Essential Psychopharmacology: Neuroscientific Basis and Practical Applications, 3rd ed. New York: Cambridge University Press; 2008.

Figure 2

Folate metabolic pathway. CBS, cystathionine b synthase; DHF, dihydrofolate; DHFR, dihydrofolate reductase; MS, methionine synthase; MT, methyltransferase; MTHFR, methylenetetrahydrofolate reductase; SAH, S-adenosylhomocysteine; SAM, S-adenosylmethionine; SHMT, serine hydroxyl-methyltransferase; THF, tetrahydrofolate. Adapted with permission from Bodnar LM et al.