September 27, 2026

Folic acid during pregnancy: dosage and benefits

Q: When should I start taking folic acid?

Ideally, at least one month before trying for a baby, and keep taking it through the first trimester (or the whole pregnancy, as your doctor indicates). That way your body has reserves from the moment the neural tube starts to form.

If you already know you’re pregnant, one of the first two things your gynecologist tells you during the first visit after confirming it is, on one hand, to ask when your last period was to calculate your week of pregnancy and, on the other, to start taking folic acid. If you don’t know yet whether you’re pregnant, check out this article on our free virtual pregnancy test.

In fact, if you visit your gynecologist to tell them you’re planning to try for a baby — something we should all do so they can give us a check-up and proper guidance — they will probably already tell you to start taking folic acid. In this article I’ll try to answer all those questions we have about folic acid: What is it? What’s it for? When should I start taking it? What dose is recommended?… Let’s get started!

Folic acid pregnancy

What is folic acid?

Realistically, we’d need to be chemists to fully understand what folic acid is, but so the rest of us mortals get it: folic acid is a vitamin, specifically vitamin B9. You find it in green vegetables, legumes, nuts, brewer’s yeast… but, unfortunately, it gets lost when cooking and even when storing food at room temperature. What you’ll actually take usually comes in little round tablets — like the ones I took, which my gynecologist called “little capsules” because they were round and plastic-like. Often the same tablets the gynecologist prescribes, or the ones you buy at the pharmacy, also contain supplements of other vitamins and minerals that pregnant women need, like Omega 3, Omega 6 and iron.

Who should take it?

Although it’s also used as a treatment for certain anemias, in recent years health organizations and governments have recommended that all pregnant women, or women planning a pregnancy, take folic acid. In fact, it’s advised to start taking it at least one month before getting pregnant, so your body has good reserves from the very beginning. And if you don’t know yet whether you’re pregnant, you can take our free online pregnancy test to get some guidance from your symptoms. And if you fancy a bit of fun, try your luck with our fun fingerprint game: it’s just a game, not a real test.

Why should you take folic acid if you’re pregnant, or even before?

It’s very important to take folic acid for these reasons: it helps prevent deformities of the placenta that could lead to miscarriage, and birth defects of the brain (anencephaly) and of the spine (spina bifida) in the baby, caused by the neural tube not closing properly at the top and bottom ends. You’ve probably heard of spina bifida, a birth defect of the spine that can lead to paralysis of the lower body, loss of bowel and bladder control, and learning difficulties. If the fetus doesn’t get enough folic acid during pregnancy it can also develop megaloblastic anemia, be born premature or have a low birth weight. The mother can develop pre-eclampsia/eclampsia, a condition that involves high blood pressure and protein in the urine. Folic acid also helps keep the uterus healthy.

As you can see, it’s extremely important to have enough folic acid reserves. That’s why, since the link between folate deficiency and neural tube defects was discovered, governments and health organizations worldwide have strengthened their recommendations for folic acid supplements in women trying to get pregnant.

Where do we find folic acid naturally?

As I mentioned earlier, folic acid can be found in the following foods:

Leafy green vegetables: spinach, escarole, Swiss chard, broccoli, asparagus and peas.
Legumes: chickpeas, lentils, dried beans and broad beans.
Fortified cereals and enriched wholegrain bread.
Nuts and seeds: walnuts, hazelnuts and sunflower seeds.
Meat is poor in folic acid, but we can find it in beef liver, and also in oily fish.

So eating a varied diet rich in these foods from before pregnancy will help you fill the folate reserves your body will need later. 🥗

How long should you take folic acid during pregnancy?

Remember that your gynecologist will give you the exact schedule, but just so you have an idea: it’s recommended to take folic acid for at least the first trimester of pregnancy, which is when the baby’s neural tube forms. Many current guidelines advise keeping it up throughout the whole pregnancy (and also while breastfeeding), often as part of prenatal vitamin complexes, because it helps prevent anemias and keeps being beneficial. In any case, always follow your doctor’s advice.

How much folic acid should you take?

The recommended daily intake of folic acid for pregnant women is between 600 µg and 800 µg. Since some of the folate already comes from food, gynecologists usually prescribe a supplement of 400 µg of synthetic folic acid. It’s been established that, for pregnant women, the maximum intake should be 800 µg.

Although a toxic level for folic acid isn’t known, some studies link a very high intake during the last trimester with a higher risk of the child developing asthma. That’s why it’s recommended to take a high-dose folic acid supplement before getting pregnant and during the first trimester — when a deficiency would be most serious — and, during the second and third trimesters, a more moderate supplement.

Does folic acid have side effects?

Taking folic acid at the recommended dose is safe and very well tolerated. In some cases it can cause mild discomfort such as nausea, stomach upset or a strange taste in the mouth, which usually goes away when you take it with meals. The important thing is not to exceed the dose your doctor has indicated and, above all, not to self-medicate: your doctor is the one who best knows what you need at each moment.

Where can you buy folic acid?

You can get folic acid at any pharmacy. There are many brands, all different and all completely effective. Let your gynecologist prescribe the brand he knows and knows works well; you can also ask your trusted pharmacist. But, since it isn’t a medicine that requires a prescription, you can also find it in other places, such as supermarkets, parapharmacies and even on Amazon.

Should men take folic acid too?

If you’re trying for a baby, folate helps fertility in both men and women. In men it contributes to sperm production. In women it contributes to the maturation of the egg and to implantation — see fertile days —, in addition to the effects we’ve already discussed during pregnancy. So it’s important to get enough through the diet, or to take a supplement, so as not to harm fertility.

FAQ

When should I start taking folic acid?

Ideally, at least one month before trying for a baby, and keep taking it through the first trimester (or the whole pregnancy, as your doctor indicates). That way your body has reserves from the moment the neural tube starts to form.

How much folic acid do I need a day?

If you’re pregnant or trying to get pregnant, the usual supplement dose is 400 µg a day, within a total recommended intake of 600 to 800 µg including your diet. Your doctor will adjust the dose to your case.

What happens if I forget to take it one day?

Nothing serious. If you forget a dose, take it when you remember, unless the next one is almost due; in that case, skip the missed one and carry on with your routine. Don’t double up to make up for it.

Can I take folic acid if I’m not pregnant and not trying?

Yes. It’s a water-soluble vitamin and, at normal doses, it’s not a problem; it can even be good for your general health. Still, if you have doubts, talk to your doctor before taking any supplement.

Is the folate in food the same as in the supplement?

The folate in food is the natural form, and the folic acid in the supplement is the synthetic form, which your body uses very well. Both count, but the supplement makes sure you reach the recommended daily dose.

Well, I hope I’ve helped clear up all the doubts you may have had about folic acid. Always remember to consult your gynecologist or doctor; it’s important, as a couple, to let them know you intend to try for a baby, because they’ll give you the right schedule for taking the folic acid supplement. And if you fancy sharing or saving the reminder, I also recommend a look at the first pregnancy symptoms and at the calculator explaining how many weeks of pregnancy you are.

Sources

To write this article I’ve relied on verifiable information from health organisations and on the classic study on folic acid and neural tube defects:

World Health Organization (WHO) — Birth defects (fact sheet)
PubMed (The Lancet, 1991) — Prevention of neural tube defects: results of the Medical Research Council Vitamin Study
NHS (United Kingdom) — Vitamins and minerals: B vitamins and folic acid
NHS (United Kingdom) — Have a healthy diet in pregnancy
MedlinePlus (U.S. National Library of Medicine) — Folic acid
Harvard T.H. Chan School of Public Health — Folic acid

Remember that this article is for information only and doesn’t replace the advice of a health professional. If you have questions about your health or you’re pregnant, always consult your doctor ❤️.