Benefits of taking folic acid and vitamin D before pregnancy

You are advised to take folic acid and vitamin D supplements (tablets) if you are trying to get pregnant. This can help prevent pregnancy complications.

Why do I need to take pregnancy supplements if I’m trying to get pregnant?

Taking folic acid supplements (tablets) does not help you get pregnant, but you are recommended to take them while you are trying to get pregnant and during the first 12 weeks of pregnancy. This is because it can improve your health and your baby’s health and help prevent serious pregnancy complications. You are also recommended to take vitamin D supplements.

Eating a healthy, varied diet will also help you to get most of the vitamins and minerals you need for a healthy pregnancy.

There are many branded pre-pregnancy supplements (vitamins) available in pharmacies and supermarkets. These are not harmful, but they can be expensive.  

Folic acid and vitamin D are the only supplements you need and it is often cheaper to buy these separately.  

Why should I take folic acid before pregnancy?

Folic acid (vitamin B9) reduces the risk of the baby having a neural tube defect. This is when the baby’s spinal cord does not develop properly. Spina bifida is one type of neural tube defect.  

When should I start taking folic acid?

Try to start taking folic acid tablets for 3 months before you get pregnant (conceive). This allows it to build up in your body to a level that gives the most protection to your future baby against neural tube defects, such as spina bifida.

As you could get pregnant within a month of trying, it is ideal to start taking folic acid tablets 3 two months before you stop contraception. If you have already stopped contraception, that’s OK, start taking it now.

Your doctor or midwife may recommend that you keep taking folic acid throughout pregnancy if you are anaemic or at risk of anaemia.

It is not harmful to take  folic acid tablets for far longer than 2 to 3 months if it is taking longer than that to get pregnant.  

How much folic acid should I take?

Most women and birthing people are advised to take a 400mcg supplement every day. You can get these from most pharmacies, supermarkets, and health food shops. Your GP may also be able to prescribe them to you.

Folic acid is a synthetic form of folate, which can be found in some food, including:  

  • spinach, kale, Brussels sprouts, cabbage, broccoli
  • beans and legumes (e.g. peas, blackeye beans)
  • yeast and beef extracts
  • oranges and orange juice
  • wheat bran and other whole grain foods
  • poultry, pork, shellfish and liver
  • some brands of breakfast cereals.

Eating foods high in folate will not be enough to protect your baby’s development. It is important to take the folic acid supplement too.

Some people need a higher dose of folic acid

You may need a 5mg supplement of folic acid if you:

Your GP can give you a prescription for 5mg folic acid supplements because they are not available over the counter.  

Taking vitamin D while trying to get pregnant

During pregnancy, Vitamin D is important because it helps your baby’s bones, teeth, kidneys, heart and nervous system to develop.  

Vitamin D may also help prevent pregnancy complications such as:

Where does vitamin D come from?

The body creates vitamin D from direct sunlight on the skin when outdoors. Vitamin D is also found in a small number of foods.

Sources include:

  • oily fish – such as salmon, sardines, herring and mackerel
  • red meat
  • liver
  • egg yolks
  • fortified foods – such as some fat spreads and breakfast cereals.

The sun is often not often strong enough in the UK for the body to make vitamin D. It’s also hard for people to get enough vitamin D from food alone.

This is why supplements are often recommended. All pregnant people are recommended to should take a 10 microgram supplement of vitamin D every day during pregnancy and while breast or chest feeding.

Should I take vitamin D supplements while trying for a baby?

There is no official advice about taking vitamin D supplements before pregnancy.

But we recommend that you start taking a 10 microgram (or 400 IU) vitamin D supplement once a day if you are actively trying to get pregnant. This will help make sure you have the right vitamin D levels from the beginning of your pregnancy.

Vitamin D deficiency

You may be at risk of not having enough vitamin D (known as vitamin D deficiency) if:

  • you have Black or Brown skin (for example, if you're of African, African Caribbean or south Asian origin)
  • you cover your skin when outside or spend a lot of time inside
  • your diet is low in vitamin D-rich foods such as eggs, meat, vitamin D-fortified margarine or breakfast cereal.
  • your BMI is above 30.

A 10 microgram (or 400 IU) vitamin D supplement a day will be enough for most people to get enough vitamin D.  

But speak to your GP if you think you are at risk of having a vitamin D deficiency or have any other concerns.

Do not take more than 100 micrograms (4,000 IU) of vitamin D a day as it could be harmful. You cannot overdose on vitamin D by being in the sun but remember to cover up or protect your skin to reduce the risk of skin damage and skin cancer.

Vitamin D deficiency and miscarriage

New research has found Vitamin D deficiency is linked to with increased risk of miscarriage.

There is not enough research yet to show that taking vitamin D before getting pregnant will help prevent miscarriage but it may help. That is why we recommend that you start taking a 10 microgram (or 400 IU) vitamin D supplement once a day while you are trying to get pregnant.

If you have had 2 or more miscarriages before we recommend that you are tested for a vitamin D deficiency. Speak to your GP or specialist. Find out more about getting referred to a doctor who specialises in miscarriage.  

Vitamin A

Do not take any supplements containing vitamin A, such as liver or fish oil. High doses of vitamin A can affect the development of the baby in the womb.

Herbal and homeopathic remedies  

Not all "natural" remedies or complementary therapies are safe in pregnancy.  

Some products used may not be of a high quality and may contain other substances, such as lead, that could be harmful.

You're also advised not to take herbal remedies if you're trying to get pregnant.

Healthy Start

If you’re more than 10 weeks pregnant or have a child under 4, the Healthy Start scheme can help you:

  • buy healthy foods like milk or fruit
  • get free vitamins

You need to be claiming certain benefits to qualify.

If you are pregnant and under 18 you can claim even if you do not receive any benefits.

If you live in Scotland you cannot get Healthy Start. You can apply for Best Start Foods instead.

If you are not a British citizen but your child is, you may still be eligible for the Healthy start scheme. Find out more on Gov.UK.

1. Sue Macdonald, Gail Johnson, Mayes’ Midwifery. (Edinburgh: Baillir̈e Tindall Elsevier, 2017), p 312.

2. NHS Choices (accessed 01/04/2018) Why do I need folic acid in pregnancy? Page last reviewed: 16/03/2016 Next review due: 16/03/2018

3. NHS Choices (accessed 01/04/2018) Spina bifida Page last reviewed: 04/05/2017 Next review due: 04/05/2020

4. NHS Choices (accessed 01/04/2018) Vitamins and minerals Page last reviewed: 03/03/2017 Next review due: 03/03/2020

Review dates
Reviewed: 29 August 2023
Next review: 29 August 2026