Pregnancy is a phase during which the need for certain nutrients increases considerably — including the long-chain omega-3 fatty acid DHA (docosahexaenoic acid). DHA is an essential component of cell membranes in the brain and retina of the eye, playing a key role in the child's development in the womb. At the same time, large-scale studies show that adequate omega-3 intake during pregnancy is associated with a reduced risk of premature birth. In this article you will find what current research says on this topic, what EFSA (the European Food Safety Authority) recommends and what matters for omega-3 intake during pregnancy. Important: always consult your doctor or midwife before taking any supplements during pregnancy.
Why is DHA so important during pregnancy?
DHA belongs to the polyunsaturated fatty acids of the omega-3 family, and the human body only synthesises it in limited quantities from the plant-based precursor ALA (alpha-linolenic acid). For the growing baby, this endogenous production is practically irrelevant — the baby depends entirely on the DHA that the mother provides via the placenta.
DHA and foetal brain development
A child's brain is largely composed of fat, and DHA makes up a significant proportion. The brain grows most intensively in the third trimester and in the first months of life after birth — a phase in which the need for DHA is especially high. DHA is a component of the cell membranes of neurons and influences their fluidity and signal transmission. Numerous observational and interventional studies have investigated whether a higher maternal DHA intake is associated with better cognitive development in children. Studies show consistent associations, although effects vary individually.
DHA and eye development
The retina of the eye also contains high concentrations of DHA. Photoreceptors — the light-sensitive cells of the retina — are particularly rich in DHA. For the healthy development of the child's visual function, an adequate supply of DHA during pregnancy and breastfeeding therefore plays an important role. Animal studies and clinical data support these relationships, though translation to humans is still being researched in detail.
EFSA health claim: DHA during pregnancy
The European Food Safety Authority (EFSA) has approved the following health claim for DHA during pregnancy and breastfeeding: "Maternal intake of DHA contributes to the normal development of the brain and eyes of the foetus and of breastfed infants."
Requirement: the mother takes daily at least 200 mg DHA in addition to the recommended daily intake of 250 mg EPA+DHA for adults, i.e. a total of at least 450–600 mg DHA+EPA per day. This claim is one of the most thoroughly investigated in EFSA's entire catalogue of health claims.
The 2018 Cochrane Review: the strongest evidence on preterm birth prevention
The most comprehensive scientific analysis of omega-3 supplementation during pregnancy is the Cochrane review by Middleton et al. from 2018. Cochrane reviews are considered the gold standard of evidence-based medicine, systematically pooling all available methodologically rigorous studies.
Middleton et al. (PMID: 30480773, Cochrane Database of Systematic Reviews, 2018) analysed 70 randomised controlled trials with a total of 19,927 pregnant women. Key findings:
- Premature births before 37 weeks' gestation were reduced by 11% (RR 0.89; 95% CI 0.81–0.97; high-quality evidence)
- Very premature births before 34 weeks' gestation were reduced by 42% (RR 0.58; 95% CI 0.44–0.77; high-quality evidence)
- Mean birth weight of children was significantly higher in the omega-3 group
- Gestational length was on average longer in the omega-3 group
- No increased risk of adverse effects was observed
Prevention of preterm birth: 70 RCTs, 19,927 women
Middleton P et al. analysed all available RCTs on omega-3 supplementation during pregnancy. Premature births <37 weeks: RR 0.89 (−11%), high-quality evidence. Very premature births <34 weeks: RR 0.58 (−42%), high-quality evidence. Additionally: higher birth weight, no adverse effects in supplementation groups.
The review authors concluded that omega-3 supplementation during pregnancy can be considered an effective measure for preventing premature birth — especially in women with low omega-3 status.
Official European recommendation: the 2024 EBCOG position
Based on available evidence — especially the 2018 Cochrane review and other RCTs — the European Board and College of Obstetrics and Gynaecology (EBCOG) published an official recommendation on omega-3 supplementation during pregnancy in 2024.
EBCOG recommendation: omega-3 during pregnancy
The European Board and College of Obstetrics and Gynaecology formulated based on available evidence an official recommendation for omega-3 supplementation during pregnancy — with the aim of reducing premature and very premature births. This is the first explicit European guideline-level recommendation of this kind for pregnant women.
The EBCOG document represents an important step in European obstetrics: for the first time, omega-3 is formulated as a supplementation recommendation for pregnant women at guideline level. The recommendation is particularly directed at women who consume little oily fish, as this group typically has low blood omega-3 levels.
How much DHA and EPA does a pregnant woman need daily?
The question of optimal dosage receives partially different answers in the specialist literature. However, the following guidance values are well supported:
| Organisation / Authority | Recommendation for pregnant women | Note |
|---|---|---|
| EFSA (health claim) | 250 mg EPA+DHA + 200 mg additional DHA | Official claim for foetus/infant |
| DGE (German Nutrition Society) | 200 mg DHA/day additional | Recommendation for pregnant and breastfeeding women |
| WHO/FAO | 300 mg DHA+EPA/day (min. 200 mg DHA) | International recommendation |
| ISSFAL | min. 200 mg DHA/day | International Society for the Study of Fatty Acids |
| Cochrane Review dose range | from 500 mg DHA+EPA/day | Studies on preterm birth prevention |
Particularly important: fish oil supplements for pregnant women must be free from heavy metals (especially mercury) and other contaminants. High-quality products are tested for these residues and present corresponding certificates. More information on quality criteria for good omega-3 supplements can be found in the buying guide.
Natural sources vs. supplementation
Oily fish as the primary source
DHA and EPA are found primarily in oily sea fish: salmon, mackerel, herring and sardines are especially rich sources. The rule of thumb is: eating two portions of oily fish per week approaches the recommended DHA intake. However, health authorities in some countries recommend limiting certain fish (e.g. tuna, swordfish) during pregnancy, as these may have higher mercury content.
When diet is insufficient
Studies show that many pregnant women do not reach the recommended DHA intake through diet alone — particularly with vegetarian or vegan eating. In these cases, targeted supplementation with purified fish oil or algae oil (which provides DHA directly from the marine food chain source and is suitable for vegans) can be an option. DHA supplements based on algae oil are well researched regarding biological efficacy and are considered a safe alternative to fish oil.
Important notice for pregnant women
Dietary supplements during pregnancy — including those based on omega-3 — should only be taken after consulting your doctor or midwife. Very high doses of omega-3 (more than 3 g/day) can influence blood clotting and should not be taken during pregnancy without medical supervision. Also, choose products specifically developed for pregnant women and tested for absence of contaminants.
DHA and cognitive development of the child: what studies show
A particularly well-researched aspect is whether prenatal DHA supplementation influences the child's cognitive and motor development after birth. Carlson et al. published a meta-analysis on this topic that pooled several intervention studies with prenatal DHA administration. The analysis found that maternal DHA supplementation significantly improved cognitive development in preterm infants at 12 to 24 months of age, including motor and language milestones. The most pronounced effects were seen in subgroup analysis for DHA doses of at least 800 mg daily initiated before week 20 of gestation.
In full-term newborns, the picture is more heterogeneous: some studies show positive effects on attention and language development; others report no differences. Overall, evidence suggests that the effects of DHA supplementation may be especially relevant when the mother's baseline status is low.
Omega-3 and pregnancy complications: other findings
Pre-eclampsia and blood pressure
Some studies have investigated whether omega-3 might also play a role in pregnancy complications such as pre-eclampsia (raised blood pressure during pregnancy). The evidence here is less clear than for preterm birth prevention, and it would be premature to derive clinical recommendations. Interested readers can consult the current evidence on PubMed.
Postnatal depression
Some observational studies have linked low omega-3 levels after birth with a higher risk of postnatal depression. Intervention studies showed in some cases positive effects of EPA-predominant omega-3 supplements on depressive symptoms in general. However, specific research on omega-3 supplementation as a protective factor against postnatal depression has not yet concluded.
Safety of omega-3 during pregnancy
High-quality fish oil and algae oil supplements are considered safe at the usually recommended doses (200–600 mg DHA+EPA daily) during pregnancy. EFSA has approved the corresponding health claim on the basis of extensive safety evaluations. Please note:
- Freedom from contaminants: choose products tested and certified for mercury, PCBs, dioxins and pesticides (e.g. Friend of the Sea, IFOS, MEG-3).
- Vitamin A-free supplements: cod liver oil contains large amounts of vitamin A (retinol), which in large doses can be harmful during pregnancy. Do not use cod liver oil — use purified fish oil or algae oil instead.
- Low doses are effective: according to the EFSA health claim, 200 mg additional DHA (above the base dose of 250 mg EPA+DHA) is sufficient to fulfil the approved claim.
- Individual medical consultation: consult a doctor before any supplementation during pregnancy.
Omega-3 from the start: the importance of timing
Studies suggest that the timing of supplementation during pregnancy is relevant. Many experts recommend starting adequate omega-3 intake in the first trimester or even before conception. The child's brain and nervous system develop throughout pregnancy — so building omega-3 reserves as early as possible appears reasonable. If you are already thinking about omega-3 before pregnancy, you will find more information in the article Omega-3 and fertility.
After the birth, the increased need continues during breastfeeding: through breast milk, DHA continues to be transferred to the baby. More information in the article Omega-3 during breastfeeding. Detailed information on dosage, product selection and practical tips specifically for pregnancy and breastfeeding can be found in the article Omega-3 for pregnant women.
Dosage recommendations at a glance
The exact dosage depends on individual starting conditions — including omega-3 index, dietary habits and any pre-existing conditions. A detailed description of general omega-3 dosage recommendations can be found in the article Omega-3 daily dosage.
For specific application during pregnancy, the following is a scientifically supported guide:
- At least 200 mg DHA daily in addition to the general recommendation of 250 mg EPA+DHA
- Many prenatal supplements combine 300–600 mg DHA + EPA per daily dose
- In the Cochrane review, studies with from 500 mg DHA+EPA daily showed the strongest effects on preterm birth prevention
- Cod liver oil is not suitable during pregnancy due to its high vitamin A content
Omega-3 for brain development after birth
DHA supply to the child does not end at birth. In the first months of life, the baby's brain continues to grow especially rapidly, and DHA remains a key component of that development. Breastfed babies receive DHA through breast milk, provided the mother is well supplied. For bottle-fed babies, DHA-enriched infant formula is now standard in Europe. More information on DHA and the baby's brain development can be found in the article Omega-3 and the brain.
Frequently asked questions
From which point in pregnancy should I take omega-3?
Many experts recommend paying attention to adequate omega-3 intake from the first trimester — or ideally even from the planning phase. Since the baby's brain grows from the start of pregnancy, early supplementation is reasonable. Discuss the timing and dosage with your doctor or midwife.
Can I cover my DHA needs during pregnancy from fish alone?
Two portions of oily sea fish per week (e.g. salmon or herring) generally provide sufficient DHA. However, during pregnancy you should limit certain fish such as tuna or swordfish due to potential mercury content. If you eat little or no fish, supplementation with tested fish oil or algae oil is possible — after consulting your doctor.
Is fish oil safe during pregnancy?
Purified fish oil tested for contaminants is considered safe at usual doses (200–600 mg DHA+EPA per day) during pregnancy. This is also shown by the safety evaluation of the 2018 Cochrane review, which included data from nearly 20,000 women. Important: cod liver oil is not suitable during pregnancy as it contains too much vitamin A (retinol). Discuss your choice of supplement with your doctor.
What is the difference between fish oil and algae oil during pregnancy?
Algae oil provides DHA directly from its original source — marine algae — and contains little or no EPA. Fish oil generally contains both fatty acids, EPA and DHA. For pregnant women following a vegan or vegetarian diet, algae oil is the preferred alternative. Studies show that DHA from algae oil is comparably bioavailable in the body to DHA from fish oil.
What does the EFSA health claim say about DHA during pregnancy?
EFSA has approved the following health claim: a daily intake of 200 mg DHA in addition to the general recommendation of 250 mg EPA+DHA for adults contributes to the normal brain and eye development of the foetus and breastfed infant. This means in practice a total intake of at least 450–600 mg EPA+DHA per day, with particular emphasis on DHA.
Medical disclaimer
This article is for general information purposes only and does not replace medical advice. All health statements are based on EFSA-authorised health claims and published scientific studies. Dietary supplements during pregnancy should in principle only be taken after consulting a doctor. The study findings mentioned in this article reflect the state of evidence at time of publication and do not replace individual medical advice. Dietary supplements are not a substitute for a balanced and varied diet.
Related articles: Omega-3 and fertility · Omega-3 during breastfeeding · Omega-3 and the brain · Omega-3 daily dosage