Prenatal DHA: what it is, how much you need and how to get it
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- Prenatal DHA softgels from fish oil. Best for: Pregnant people who eat little seafood. See options on Amazon
- Vegan prenatal DHA from algal oil. Best for: Vegetarian and vegan pregnancies. See options on Amazon
- Prenatal multivitamin with DHA. Best for: People who want one product covering prenatal nutrients and DHA. See options on Amazon
What is DHA in prenatal vitamins?
DHA (docosahexaenoic acid) is a long-chain omega-3 fat. NIH explains that long-chain omega-3s, especially DHA, are critical for fetal growth and development, particularly the brain and eyes. DHA concentrates in the brain and retina and builds up most rapidly during the third trimester.
Many people assume their prenatal vitamin covers it. NIH reports that omega-3s are not usually included in standard multivitamins, and only 35% to 39% of prescription and nonprescription prenatal supplements contain DHA. Check your label; our prenatal vitamin guide explains how to read the rest of the formula.
How much DHA do you need during pregnancy?
There is no official RDA for DHA or EPA. NIH notes that expert groups recommend:
| Recommendation | Amount |
|---|---|
| Women of childbearing age, DHA plus EPA | At least 250 mg a day |
| Extra DHA during pregnancy | 100 to 200 mg a day |
| Seafood during pregnancy | 8 to 12 ounces a week, lower in mercury |
| Plant omega-3 (ALA) in pregnancy | 1.4 g a day (Adequate Intake) |
Most pregnant women miss these targets. NIH cites survey data showing pregnant women aged 20 to 40 average about 60 mg of DHA a day from food and about 77 mg from food and supplements.
Seafood first, supplements to fill the gap
Seafood is the best source of long-chain omega-3s, and NIH notes that seafood intake in pregnancy is linked with better cognitive development measures in young children. Eating 8 to 12 ounces a week provides about 250 mg a day of DHA plus EPA. NIH says U.S. agencies encourage choosing lower-mercury options such as salmon, anchovies, sardines, Pacific oysters and trout, and that studies show the benefits of seafood in pregnancy outweigh the potential risks.
Supplements help most if you eat little or no seafood. NIH notes that research indicates long-chain omega-3s reduce the risk of preterm birth.
Fish oil or algal DHA?
NIH says prenatal omega-3 supplements come from marine sources such as fish oil or from algae. Algal oil suits vegetarian or vegan diets; see our algae omega-3 guide.
Amounts vary. In a 2024 evaluation of 68 prenatal supplements that contained omega-3s, NIH reports the average DHA was 368 mg in U.S. products. A 2024 guideline cited by NIH found intakes up to 1,000 mg a day of DHA, or DHA plus EPA, raise no safety concerns in pregnancy.
Safety and what to avoid
- Cod liver oil: NCCIH notes it also contains vitamins A and D in amounts that vary, and vitamin A can be harmful in excess. NIH warns that too much preformed vitamin A in pregnancy can cause birth defects. Prefer a DHA product without added vitamin A unless your clinician says otherwise.
- Blood thinners: fish oil can have antiplatelet effects at high doses; tell your clinician.
- Common side effects: NCCIH lists unpleasant taste, bad breath, heartburn, nausea and diarrhea, usually mild.
How to choose a prenatal DHA
- Check your prenatal first; many do not include DHA.
- Look for DHA in mg on the label, aiming to reach the 100 to 200 mg extra experts suggest on top of a healthy baseline.
- Pick the source: fish oil or algal oil for vegetarians.
- Avoid added vitamin A and cod liver oil unless advised.
- Continue while breastfeeding if your clinician recommends it; see our postnatal vitamin guide.
What to look for when you buy
Prenatal DHA softgels from fish oil
Best for: Pregnant people who eat little seafood
A dedicated DHA softgel adds the extra 100 to 200 mg of DHA experts suggest during pregnancy, and many supply more.
Watch out: Check for added vitamin A. Tell your clinician if you take blood thinners.
See options on AmazonVegan prenatal DHA from algal oil
Best for: Vegetarian and vegan pregnancies
NIH notes algal oil is a vegetarian source of long-chain omega-3s for pregnancy.
Watch out: Check the DHA mg per serving and that the softgel shell is plant-based.
See options on AmazonPrenatal multivitamin with DHA
Best for: People who want one product covering prenatal nutrients and DHA
Combining products avoids stacking. Compare the DHA amount with the extra 100 to 200 mg target.
Watch out: Some combination products have modest DHA; read the mg. Do not double prenatal vitamins.
See options on AmazonQuestions people ask
- What is DHA in prenatal vitamins?
- An omega-3 fat important for a baby's brain and eye development. Only about a third of prenatal supplements include it, so check the label.
- How much DHA should I take while pregnant?
- Experts cited by NIH suggest at least 250 mg a day of DHA plus EPA, with an extra 100 to 200 mg of DHA during pregnancy. Ask your clinician what fits your diet.
- Can I get enough DHA from fish?
- Eating 8 to 12 ounces a week of lower-mercury seafood provides about 250 mg a day of DHA plus EPA, according to NIH.
- Is too much DHA harmful in pregnancy?
- A 2024 guideline cited by NIH found up to 1,000 mg a day of DHA, or DHA plus EPA, raises no safety concerns. Avoid products with added vitamin A unless advised.
Sources
- Dietary Supplements and Life Stages: Pregnancy (ods.od.nih.gov), NIH Office of Dietary Supplements
- Omega-3 Supplements: What You Need To Know (nccih.nih.gov), National Center for Complementary and Integrative Health
- Omega-3 Fatty Acids: Fact Sheet for Health Professionals (ods.od.nih.gov), NIH Office of Dietary Supplements