Folic acid and pregnancy vitamins: what to take, how much and when

If you’re trying for a baby or you’ve just found out you’re pregnant, there are 2 supplements the NHS recommends: folic acid and vitamin D. Most other nutrients can come from a healthy, varied diet. Here’s what to take, how much, and what to avoid.

Folic acid: 400 micrograms a day

Folic acid can help prevent birth defects known as neural tube defects, including spina bifida. The NHS advises taking 400 micrograms of folic acid every day from before you’re pregnant until you’re 12 weeks pregnant.

If you didn’t take it before conceiving, start as soon as you find out. You can buy it at pharmacies and supermarkets.

Who needs the higher 5mg dose

Some people have a higher chance of a pregnancy affected by a neural tube defect, and are advised to take 5 milligrams (5mg) of folic acid a day until they’re 12 weeks pregnant. This applies if:

you or the baby’s biological father have a neural tube defect
you or the baby’s biological father have a family history of neural tube defects
you’ve had a previous pregnancy affected by a neural tube defect
you have diabetes
you have sickle cell disease or thalassaemia
you take anti-epilepsy medicine
you take anti-retroviral medicine for HIV
you take other medicines that affect folic acid, so check with your GP or pharmacist

If any of these apply to you, speak to a GP, ideally before you start trying. They can prescribe the higher dose.

Vitamin D: 10 micrograms a day

You need 10 micrograms of vitamin D each day. It’s recommended that pregnant and breastfeeding women take a daily supplement containing this amount between September and March.

You may need to take it all year if you have dark skin (for example, if you’re of African, African-Caribbean or South Asian origin), you usually cover your skin when you’re outside, or you spend a lot of time indoors. Don’t take more than 100 micrograms (4,000 IU) a day, as it could be harmful.

Vitamin A: what to avoid

Too much vitamin A could harm your baby. So in pregnancy:

don’t take cod liver oil or any supplements containing vitamin A (retinol)
avoid liver and liver products, which are high in vitamin A
if you take a multivitamin for your folic acid, make sure it doesn’t contain vitamin A (retinol)

Iodine

Iodine helps make thyroid hormones. The NHS says adults need 140 micrograms a day. The British Dietetic Association says you need more in pregnancy (it quotes 200 micrograms), and that not getting enough iodine in pregnancy may affect a baby’s brain development.

Good sources include dairy products, eggs, sea fish and shellfish. Some plant-based drinks are fortified with iodine, but not all, so check the label.

The NHS pregnancy vitamin advice doesn’t include an iodine supplement. If you don’t eat much dairy or fish, ask your midwife, GP or a dietitian. If your pregnancy supplement contains iodine, the British Dietetic Association suggests checking it doesn’t provide more than 150 micrograms. Don’t use seaweed or kelp supplements as a source of iodine.

Iron, calcium and vitamin C

You can usually get these from your diet:

Iron: lean meat, green leafy vegetables, dried fruit, nuts and fortified cereals. If your iron is low, your GP or midwife will advise on supplements.
Calcium: dairy foods, green leafy vegetables, tofu, fortified soya drinks and bread, and sardines.
Vitamin C: citrus fruit, peppers, berries, broccoli and potatoes.

If you’re vegetarian or vegan, it can be harder to get enough iron and vitamin B12, so talk to your midwife or GP about whether you need a supplement.

Oily fish

Oily fish such as salmon, mackerel and sardines are good for you, but have no more than 2 portions a week in pregnancy, as they can contain pollutants. Remember that cod liver oil isn’t suitable, because of its vitamin A.

Free vitamins with Healthy Start

In England, Wales and Northern Ireland, you may be able to get a Healthy Start card if you’re more than 10 weeks pregnant or have a child under 4, and your family gets certain benefits, for example:

Universal Credit, with family take-home pay from work of £408 a month or less
Pension Credit (including the child addition)

If you’re under 18 and pregnant, you can get a card until your baby is born, even if you don’t get any of these benefits.

The card is topped up every 4 weeks with money for healthy food and milk: £4.65 a week from the 10th week of pregnancy, £9.30 a week for babies under 1, and £4.65 a week for children aged 1 to 4 (from April 2026). If you have a Healthy Start card, you can also get free Healthy Start vitamins containing folic acid, vitamin C and vitamin D to take in pregnancy and until your baby’s first birthday, plus vitamin drops for children from birth to 4. In England and Wales, ask your midwife or health visitor where to collect them. In Northern Ireland they’re posted to you.

If you live in Scotland, all pregnant women can get free vitamins from their health board, so ask your midwife. You may also get Best Start Foods, which is £22.40 every 4 weeks in pregnancy, if you get certain benefits (or if you’re under 18).

Folic acid in flour from December 2026

From December 2026, non-wholemeal wheat flour in the UK must have folic acid added by law, at 250 micrograms per 100g of flour. You should still take a 400 microgram supplement every day if you’re pregnant or trying.

Questions people ask

When should I start taking folic acid?

From before you’re pregnant, so it’s worth starting as soon as you begin trying or think you might get pregnant. If you’re already pregnant and haven’t been taking it, start now and carry on until 12 weeks.

Is a pregnancy multivitamin better than folic acid on its own?

Either is fine, as long as it gives you 400 micrograms of folic acid and 10 micrograms of vitamin D and doesn’t contain vitamin A (retinol).

Do I need 5mg of folic acid if I have type 1 diabetes?

Yes, the NHS advises 5mg for anyone with diabetes. Speak to your GP before you start trying. Our type 1 diabetes and pregnancy guide covers the rest of your care.