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Folic acid when planning a pregnancy

Folic acid is the man-made version of the vitamin folate. It's also called vitamin B9.

Women who can get pregnant should take 400 micrograms (mcg) of folic acid in a supplement every day. It's best to take folic acid even when you do not plan to get pregnant.

If you do not take folic acid already, it's best to:

  • start taking folic acid at least 3 months before you become pregnant
  • continue to take folic acid throughout your pregnancy

Ask your pharmacist about the best product for you.

You cannot get the amount of folate you need from food alone. But it's still important to include foods high in folate in your diet. For example, green leafy vegetables, legumes or citrus fruits. Some foods are fortified with folic acid.

Benefits of folic acid

Your baby's spine develops fully during the first month of pregnancy.

Folic acid supports your baby’s spine and brain development. This helps reduce the risk of neural tube defects (NTDs) such as spina bifida or hydrocephalus.

Neural tube defects (NTDs)

There is a higher risk of having a baby with a NTD if you have:

  • an NTD or other people in your family have an NTD
  • obesity
  • type 1 or type 2 diabetes

There is also a higher risk if there is a history of NTDs in your partner's family.

In these cases, your GP may prescribe a higher dose of folic acid (5 mg).

Who can take folic acid

Most adults can take folic acid.

But ask your GP for advice if you:

Folic acid medicines

B vitamins and folic acid

Page last reviewed: 19 March 2026
Next review due: 19 March 2029