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Folic acid when planning a pregnancy

It's important to take a folic acid supplement (vitamin B9) for at least 3 months before you become pregnant.

Folic acid supports your baby’s spine and brain development. Your baby's spine develops fully during the first month of pregnancy. Folic acid helps reduce the risk of neural tube defects (NTDs) like spina bifida.

Doctors advise that you continue to take a folic acid supplement throughout your pregnancy.

The recommended dose is 400 micrograms of folic acid supplement every day. Ask your pharmacist about the best product for you.

It is not possible to get the amount of folic acid you and your baby need from food alone. Your body will be drawing on all your nutrients when you become pregnant.

A 400 microgram supplement and a healthy diet will help make sure you and your baby are healthy.

Neural tube defects (NTDs)

Some women may be at a higher risk of having a baby with a NTD.

The risk is higher if:

  • you have an NTD, for example spina bifida or hydrocephalus
  • your partner's family have a history of NTDs
  • you have obesity
  • you have type 1 or type 2 diabetes

In these cases, a higher supplement of folic acid (5 mg) may be recommended.

Folic acid can also affect certain medicines you may be taking. For example, for epilepsy. Ask your GP for advice if you have any doubts.

Find more information on folic acid

Page last reviewed: 30 September 2022
Next review due: 30 September 2025