Taking a prenatal vitamin as directed is recommended for pregnant women, and ACOG and the Academy of Nutrition and Dietetics both advise it. But “safe” depends on the specific product. The U.S. has no federal definition of a prenatal vitamin, and the FDA doesn’t check supplements before they’re sold, so what’s on the label may not match what’s in the bottle.

The short version

  • Keep taking yours. ACOG and the Academy of Nutrition and Dietetics recommend a daily prenatal vitamin during pregnancy, according to the NIH.
  • No pre-sale check. The FDA doesn’t review dietary supplements for safety, effectiveness, or labeling before they’re sold. Companies are responsible for making them safe and labeling them truthfully.
  • Testing has found gaps. In a 2023 federal review of 12 over-the-counter prenatals, 11 had at least one nutrient outside acceptable limits compared with the label, and 6 had trace amounts of lead or cadmium, though not at levels the FDA considers a health concern.
  • A tested product is the safer bet. Look for a seal from U.S. Pharmacopeia (USP), NSF, or ConsumerLab.
  • Don’t stop over this. If your bottle has no seal, keep taking it and ask your provider or pharmacist about switching.

How prenatal vitamins are regulated

Over-the-counter prenatal vitamins are dietary supplements, which the FDA regulates differently from medicines. The FDA’s own summary says:

  • It doesn’t review dietary supplements for safety and effectiveness or their labeling before they’re sold in stores or online.
  • Supplement companies are responsible for making sure their products are safe and that label claims are truthful.
  • The FDA monitors the market, including adverse event reports and complaints, and can act against an unsafe product after it’s on sale.

See the FDA’s Questions and Answers on Dietary Supplements.

Prenatals also have no standard recipe. The NIH notes that no federal definition says what a prescription or over-the-counter prenatal supplement must contain, so formulas vary a lot. Some leave out iodine or choline, some use a form of folate other than folic acid, and many gummies have no iron or calcium. See Prenatal Vitamin Questions, Answered.

What testing has found

Several independent checks have compared prenatal vitamins with their labels. The NIH summarizes them:

Check What it found
2023 U.S. Government Accountability Office review of 12 over-the-counter prenatals 11 of 12 had at least one nutrient outside acceptable limits compared with the label, using U.S. Pharmacopeia thresholds. 6 of 12 had trace amounts of lead or cadmium, not at levels likely to cause a health concern by FDA measures.
Analysis of 51 samples from 26 prenatals commonly used in Canada 14 samples had more lead than the limit set by California’s Proposition 65 and U.S. Pharmacopeia (0.5 mcg a day). 3 samples went over known upper limits for aluminum and inorganic arsenic.
2023 analysis of more than 20,000 supplements, including 421 prenatals Of 69 products that contained all six key pregnancy nutrients (vitamin A, vitamin D, folate, calcium, iron, and long-chain omega-3s), only one, which wasn’t a prenatal, matched the target doses researchers calculated.

What this does and doesn’t mean

These results don’t show that prenatal vitamins are dangerous. The federal review found trace metals in half of the products it tested but not at levels the FDA considered a concern, and the nutrient differences were departures from the label, not necessarily harmful amounts. The Canadian analysis tested products sold in Canada, so it may not apply to every U.S. brand.

They do show that two bottles with the same label can differ, and that you can’t tell which is which from the label alone. That’s the reason independent testing matters.

How to choose a safer prenatal

  • Look for an independent testing seal. Three groups test supplements: U.S. Pharmacopeia (USP), NSF, and ConsumerLab. The NIH says a tested product is more likely to be made properly, to contain the ingredients and doses on the label, and to be free of harmful levels of contaminants.
  • Don’t rely on “prescription.” Prescription and store-brand prenatals differ in what they contain, and neither is guaranteed to match its label. In one NIH-cited comparison, prescription products had more folic acid and store brands had more iodine, calcium, vitamin A, and vitamin D.
  • Read the “other ingredients.” Some prenatals add herbs or probiotics. Many of these haven’t been well studied in pregnant women, according to the NIH.
  • Match the label to your needs. Check for folic acid, iron, iodine, and choline. See Prenatal Vitamin Questions, Answered.
  • Store it safely. Keep prenatal vitamins out of children’s reach, because the iron in them can poison a small child. See Iron Supplements in Pregnancy.
  • Report problems. If a vitamin makes you sick, tell your provider. The FDA also collects reports of reactions to supplements.

What to do now

  • Check your bottle for a USP, NSF, or ConsumerLab seal.
  • If it doesn’t have one, keep taking it and ask your provider or pharmacist at your next visit whether to switch.
  • Look at the “other ingredients” for herbs or probiotics, and ask your provider about any you don’t recognize.
  • Don’t double up on vitamins to be safe. More isn’t better, and amounts add up.

Related reading

Sources

Updated November 2026. This article is for general information and is not a substitute for advice from your health care provider.