Normal Reference Range for Folic Acid in Pregnant Women

Folic acid, also known as vitamin B9, is a water-soluble vitamin. A daily dose of 0.4 mg of folic acid is recommended to prevent neural tube defects in the fetus. What, then, is the normal reference range for folic acid levels in pregnant women?

Normal Folic Acid Range in Pregnant Women

The normal serum folic acid concentration in pregnant women ranges from 15 to 54 nmol/L. Folic acid (vitamin B9) is a water-soluble vitamin. A dose of 0.4 mg/day is used for the prevention of fetal neural tube defects, whereas 5 mg/day is typically prescribed for the treatment of anemia. Therefore, when purchasing folic acid supplements, pregnant women should select the appropriate dosage based on their specific needs. Although folic acid is widely present in both plant- and animal-derived foods—particularly abundant in animal liver—it is highly sensitive to heat and prone to oxidation during cooking, which compromises its stability and bioavailability.

During pregnancy, women should consume high-quality protein-rich foods such as eggs, milk, lean meat, and beef. Additionally, they should ensure adequate intake of foods rich in vitamins and trace elements—for example, citrus fruits (e.g., oranges and tangerines), bananas, apples, leafy greens (e.g., spinach and Chinese cabbage), celery, mushrooms, enoki mushrooms, and tofu. Whole grains—including millet, rice, buckwheat flour, and oat flour—should also be included regularly. A well-balanced diet supports optimal physical development for both mother and baby.

Consequently, only minimal amounts of folic acid can be obtained from dietary sources alone, and the bioavailability of naturally occurring folate is relatively low. Thus, women are advised to take appropriate, supplemental folic acid during the preconception and pregnancy periods. We hope this article has been helpful to you!