Folic acid is used to prevent fetal neural tube abnormalities and should be taken orally during the first 3 months of pregnancy and continued until the third trimester, after which it is not necessary to take it again. Folic acid is usually taken once a day at 0.4 mg, and the amount of folic acid can be increased or not depending on your condition. If you have metabolic disorders, you should continue to take 0.8mg per day orally and continue to take it until the third month of pregnancy, or even for six months. Folic acid, if taken too much orally without permission, may cause the occurrence of gastrointestinal disorders and even bleeding stools of dark green color. Therefore, when increasing the dose of the drug, it is important to have a check of folic acid metabolism to avoid taking the drug indiscriminately and causing adverse reactions.