From the Guidelines
The recommended dose of folic acid during the first trimester of pregnancy is 0.4 to 0.8 mg (400 to 800 μg).
Key Points
- The USPSTF recommends that all women planning or capable of pregnancy take a daily supplement containing 0.4 to 0.8 mg (400 to 800 μg) of folic acid 1, 2.
- This dose is recommended to start at least 1 month before conception and to continue daily supplements through the first 2 to 3 months of pregnancy 1.
- The American College of Medical Genetics and Genomics also recommends a daily folic acid intake of 400 μg (0.4 mg) in all women of child-bearing age, with a higher dose of 4,000 μg (4 mg) recommended for high-risk women 3.
- High-risk women include those with a personal, family, or prior pregnancy history of neural tube defects, type 1 diabetes mellitus, or exposure to high-risk medications during early pregnancy 3.
- The evidence suggests that folic acid supplementation at usual doses is not associated with serious harms 1.
From the FDA Drug Label
The usual therapeutic dosage in adults and children (regardless of age) is up to 1 mg daily... 0.8 mg for pregnant and lactating women, but never less than 0. 1 mg/day. The recommended dose of folic acid during the first trimester of pregnancy is 0.8 mg daily 4.
- This dose is specified for pregnant women.
- It is essential to note that this dose is for pregnant and lactating women in general, and the label does not provide different recommendations for the first trimester specifically.
From the Research
Folic Acid Dosage Recommendation
The recommended dose of folic acid during the first trimester of pregnancy is:
- 400 micrograms per day, as stated in the study 5
- This dose is recommended to be taken from preconception until the end of the first trimester to prevent neural tube defects (NTDs) 5
- A daily dosage of 400 micrograms is also recommended by other studies, including 6 and 7
Rationale for the Recommended Dosage
The recommended dosage is based on the following rationale:
- Folic acid is crucial for the synthesis of nucleic acids and proteins, and its deficiency can lead to NTDs 5
- The first trimester is a critical period for neural tube closure, and decreased blood folic acid levels can inhibit DNA replication and repair, leading to NTDs 5
- Studies have shown that supplementation with 400 micrograms of folic acid per day can reduce the risk of NTDs by 72% 8
Special Considerations
- Women who have had a previous pregnancy affected by a neural tube defect or other folate-sensitive congenital anomaly may require a higher dose of folic acid, typically 4-5 mg per day 9, 7
- Women with complex risks, such as genetic or medical conditions, may require personalized approaches to folic acid supplementation, including higher doses or alternative forms of folate 9