If you are newly pregnant, you can just pick a supplement with the right amount of folic acid and take it according to your own folic acid metabolism utilization rate, there is no such thing as which one is best.
If folic acid metabolism ability is normal, in the pre-pregnancy preparation stage or after pregnancy should be supplemented with 0.4 grams of folic acid daily dose.
If folate metabolism is moderately impaired, the folate level needs to be increased and adjusted to 0.8 grams daily. If the folate metabolism is severely impaired, the folate level needs to be increased and adjusted to 1.2 grams per day.
There is no definitive comparison of which folic acid is better, and pregnant women can use the results of folate metabolism testing to select supplements containing the appropriate folate dose for use. As long as the folic acid supplementation dose is up to standard, you can try to prevent fetal neural tube development malformation. The specific dosage can be taken under the guidance of a doctor.