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Is a multivitamin safe during pregnancy?

Written by the Full Measure editorial team, which sells supplements. Approved for publication by the Full Measure owners. Updated .

Drafted with AI assistance from the sources listed below. How we write these

Quick answer

NIH says a daily prenatal vitamin may be needed to meet needs for folic acid, iron, iodine and vitamin D, and that too much preformed vitamin A can cause birth defects, with an upper limit of 3,000 mcg a day. Prenatal multis generally leave out retinol. Ask your doctor which product suits you.1,2,3

Key facts

  • NIH reports that the American College of Obstetricians and Gynecologists recommends a daily prenatal vitamin in pregnancy.1
  • Too much preformed vitamin A (retinol) in pregnancy can raise the risk of birth defects, with an upper limit of 3,000 mcg a day for adult women and 2,800 mcg for teens; beta-carotene does not carry this risk.1,2
  • In a national survey of 1,003 pregnant US women, supplement use raised the share above the upper limit to 27.9% for iron and 33.4% for folic acid.1
  • US prenatal multis typically hold 800 or 1,000 mcg of folic acid, against the 400 mcg a day recommended for women who could become pregnant.1
  • NIH says results from one multivitamin cannot be applied to others, because no standard formula exists.1

What does NIH say about multivitamins in pregnancy?

During pregnancy, a daily prenatal multi can help supply enough folic acid, iron, iodine and vitamin D. A doctor might also suggest separate iodine and choline, which prenatal multis often lack or contain only in small amounts.3

NIH reports that the American College of Obstetricians and Gynecologists recommends a daily prenatal vitamin in pregnancy, and that the Dietary Guidelines for Americans say this may be necessary to meet needs for folate or folic acid, iron, iodine and vitamin D. For women who follow a vegetarian or vegan diet, it says to consult a health care provider about iron, vitamin B12, choline, iodine and other nutrients.1

NIH adds that consumers should consider a product designed for their age, sex and life stage, such as pregnancy.1

Why is vitamin A the nutrient to check?

Too much preformed vitamin A (retinol) during pregnancy can cause birth defects. Beta-carotene does not carry this risk, and prenatal multis generally leave retinol out.1,2,3

NIH lists the upper limit for preformed vitamin A as 2,800 mcg a day for pregnant teens and 3,000 mcg for pregnant women, counting food, drinks and supplements together. A label that gives vitamin A as beta-carotene is a different case, since beta-carotene has no upper limit.1,2

Can a prenatal multi push iron or folic acid past the limit?

In a nationally representative sample of 1,003 pregnant US women, most of whom likely took a prenatal multi, supplement use lowered the share with too little vitamin A from food, but it also raised the share above the upper limit: 27.9% for iron and 33.4% for folic acid.1

NIH explains that the amount of folic acid in US prenatal multis is typically 800 or 1,000 mcg, well above the 400 mcg recommended to reduce the risk of neural tube defects in babies. The upper limit for folic acid from supplements and fortified foods is 1,000 mcg, and iron's is 45 mg for pregnancy.1,4,5

Going over an upper limit is more likely when a multi is combined with single vitamin or mineral supplements, or with fortified foods and drinks such as breakfast cereals.1,3

What do trials of multivitamins in pregnancy show?

NIH describes a meta-analysis of 20 randomized trials in 141,849 pregnant women, nearly all in low- or middle-income countries. Compared with iron and folic acid alone or placebo, multivitamins went with 12% lower odds of low birth weight, 8% lower odds of small size for gestational age and 10% lower odds of preterm birth. They had no beneficial or harmful effect on stillbirth or newborn deaths.1

The one trial in a high-income country, in the United Kingdom, found no effect on those outcomes. NIH says results from one multivitamin cannot be applied to others, since no standard formula exists.1

What about the first trimester, regular multis and syrups?

NIH says the critical period for folic acid begins at least 1 month before conception and runs through the first 2 to 3 months of pregnancy. It reports that the CDC recommends 400 mcg a day for women who could become pregnant.1,4

The sources checked do not address multivitamin syrups, or any named brand, in pregnancy. That is not a finding either way, so ask your doctor or pharmacist, and compare the vitamin A and iron amounts on the label with the limits above.

Who should ask a doctor about a multivitamin in pregnancy?

  • Anyone taking other single vitamins or mineral products, or eating many fortified foods, on top of a multivitamin.1,3
  • Anyone using a regular or high-potency multivitamin, which may list retinol or high iron.1
  • Anyone following a vegetarian or vegan diet.1
  • Anyone who takes levothyroxine, an antibiotic, methotrexate or an epilepsy medicine, which can interact with minerals or folic acid.1

Ask your doctor, and bring the Supplement Facts panel of everything you take.

Questions people ask

Are vitamins safe during pregnancy?

NIH says a daily prenatal vitamin may be needed for folic acid, iron, iodine and vitamin D, and that too much preformed vitamin A can cause birth defects. Ask your doctor which products suit you.1,2

Is a multivitamin safe for pregnant women in the first trimester?

NIH says the critical period for folic acid starts at least 1 month before conception and runs through the first 2 to 3 months of pregnancy. Vitamin A as retinol is the nutrient to check. Ask your doctor.1

Is a regular multivitamin safe for pregnant women?

NIH says prenatal multis generally leave out retinol, and suggests choosing a product designed for pregnancy. Regular multis can list retinol, so check the label and ask your doctor.1,3

Is multivitamin syrup safe in pregnancy?

The sources checked do not address syrups. NIH says no standard multivitamin formula exists, so read the label for vitamin A and iron amounts and ask your doctor or pharmacist.1

Is a brand-name multivitamin safe during pregnancy?

NIH says results from one multivitamin cannot be applied to others. Read the Supplement Facts panel for vitamin A, folic acid and iron, and ask your doctor about that product.1

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Sources

  1. National Institutes of Health, Office of Dietary Supplements. Multivitamin/mineral Supplements: Fact Sheet for Health Professionals. Updated July 17, 2024. Opened 2026-10-01.
  2. National Institutes of Health, Office of Dietary Supplements. Vitamin A and Carotenoids: Fact Sheet for Consumers. Updated March 10, 2025. Opened 2026-10-07.
  3. National Institutes of Health, Office of Dietary Supplements. Multivitamin/mineral Supplements: Fact Sheet for Consumers. Updated February 15, 2024. Opened 2026-10-07.
  4. National Institutes of Health, Office of Dietary Supplements. Folate: Fact Sheet for Consumers. Updated November 1, 2022. Opened 2026-10-07.
  5. National Institutes of Health, Office of Dietary Supplements. Iron: Fact Sheet for Health Professionals. Updated September 4, 2025. Opened 2026-10-07.

This page is information, not medical advice. Talk to your doctor or pharmacist about your own situation.