The daily recommended intake of folic acid for all women in childbearing age is at least 400 micrograms (mcg), or 0.4 milligrams (mg).You should take folic acid for at least one month before conception, it reduces the risk of neural-tube defects, such as spina bifida, by up to 70 percent, according to the Centers for Disease Control and Prevention.
During pregnancy, the recommended dose jumps to 600 to 800 mcg, or 0.6 to 0.8 mg. Of course, some women’s needs are different. If you have a family history of neural-tube defects, you should probably get 4,000 mcg (4 mg) of folic acid a day. Talk to your doctor about how much you need before and after you conceive.
You can buy folic acid supplements at the drugstore or you can take a prenatal or regular multivitamin. If you do take a multivitamin, make sure it doesn’t contain more than the recommended daily allowance of 770 mcg RAE (2,565 IU) of vitamin A unless it’s all in the form of beta-carotene. (Getting too much of a certain kind of vitamin A can cause birth defects.) If you’re unsure what to take, ask your healthcare provider to recommend a supplement for you.
Folic acid is a water-soluble vitamin, so excess will be flushed out of your body if you consume too much. However for some women, getting too much folate may hide a B-12 deficiency, which can sometimes be a problem for vegetarians. Ask your doctor or midwife if you think you may be at risk.
