Maternal Health

Omega-3s and Pregnancy:
Why DHA is Essential for Mum and Baby

Why mums need Omega-3 before, during, and after pregnancy

  • DHA omega-3 is an essential nutrient for mum and baby
  • Babies are completely dependent on mum to supply DHA
  • Pregnant women in the United States consume far too little DHA

DHA omega-3 is an essential nutrient during pregnancy.  It is required for the normal development of an infant’s brain, eyes, nervous system and immune system while in the womb [1]. There are lifelong benefits for mum and child when mom consumes healthy amounts of DHA during pregnancy. Consuming too little DHA during pregnancy has been shown to put children at risk for lower IQ and poorer social and communication skills at elementary-school age [2-4]. DHA omega-3 is found naturally in fatty fish, such as salmon and herring, and in dietary supplements.

Babies are completely dependent on their mom to supply DHA

Mum is the only source of DHA omega-3 for a developing baby. Getting enough DHA during pregnancy provides nutrition for the baby’s growing immune and nervous systems. It is especially important for mum to get enough DHA during the last trimester of pregnancy because that is when the baby’s brain and eyes are rapidly developing. DHA is an integral component of the brain and eyes.

The baby’s need for enough DHA is so strong that he or she will deplete mum of DHA if mum’s supply is low. This is why mums need to consume enough DHA for both herself and her baby. In addition, because eye development and vision are not fully developed at birth, feeding the baby healthy levels of DHA from breast milk or formula helps vision continue to develop [5].

About one in ten women experience melancholy or low moods after giving birth. Healthy levels of DHA have been shown to support healthy moods in women before and after birth [6-8].

Most pregnant women consume far too little DHA

Pregnant women in North America consume far too little DHA; most consume less than 100 mg per day. Women following vegetarian or vegan diets consume even less. Walnuts, chia, and flax seeds contain a different form of omega-3; these nuts and seeds do not provide DHA [9-12].  Even if women consume high amounts of flax seeds while breastfeeding, she will not have sufficient amounts of DHA in her breast milk for her infant [13].

How much do you need?

Neither mum nor baby can make DHA in the body so it must be consumed through the diet or from supplements. The minimum recommended amount of DHA during pregnancy is 200-300 mg per day but nutrition experts recommend that women get 300 – 600 mg DHA per day during pregnancy and while breastfeeding.  In the last trimester of pregnancy, up to 900 mg of DHA is suggested [14-17].

Minimum Daily DHA Intake Recommendations During Pregnancy and Breastfeeding [ 13-16 ]
United States experts 300 – 900 mg DHA
International Infant Research Group 200 mg DHA
World Health Organization (WHO) 300 mg EPA+DHA; at least 200 mg as DHA

Where to get DHA

Salmon, sardines, herring, and high-quality tuna provide the richest dietary sources of DHA.  Fish also provides lean protein and some minerals, but many pregnant women don’t eat fish regularly, or they eat fish that has very low levels of DHA (like tilapia).  In addition, many pregnant women don’t eat fish due to worry over potential environmental toxins, such as mercury, lead, and PCBs.

The U.S. government* recommends that women who are pregnant or breastfeeding eat 8-12 ounces of fish a week that is low in mercury; that’s 2-3 servings of fish a week [18]. This is why it’s important to be selective about fish or to consume fish oil supplements that have been purified. Purified fish oil is available in capsules and liquids.

Selecting fish oil supplements that have been rigorously tested for quality and purity and certified by an independent third party, such as NSF® International or the International Fish Oil Standards Program™, provides reliable assurance.

Getting sufficient omega-3 nutrition during pregnancy supports lifelong health for mum and child.

Note: The U.S. FDA and U.S. EPA recommend that women who may become pregnant, who are pregnant or breastfeeding eat 8to 12 ounces per week. Avoid eating shark, swordfish, king mackerel, tilefish, orange roughy, and marlin, and limit white albacore tuna to no more than 6 ounces per week. For more information about fish and seafood in your area, go to the U.S. EPA Fish Consumption Advisory website

By Gretchen Vannice, MS, RDN ©  All rights reserved

About the author: Gretchen Vannice is a registered dietician nutritionist and independent consultant who specialises in omega-3 fatty acids and natural foods. She is a strategist, trainer, speaker, and author. Gretchen is lead author of the 2014 Position Paper on Healthy Dietary Fats for Adults, written for the Academy of Nutrition and Dietetics, and author of Live Long and Thrive with Omega-3s. A consumer’s guide to fish, fish oil, nuts, and seeds. She can be reached at

Disclaimer:  Written by an independent nutritional expert, this information is provided for educational purposes only.

It is not intended as medical advice. Always consult your healthcare provider for medical advice.


[1]   Innis SM. Brain Res 2008;1237:35-43.
[2]  Bakker EC, Hornstra G, Blanco CE, et al. Eur J Clin Nutr 2007:1-6.
[3]  Krabbendam K, Bakker E, et al. Prostaglandins, Leukot Essent Fatty Acids 2007;76(1):29-34.
[4]  Hibbeln JR, Davis JM, Steer C. Lancet 2007;369:578-585.
[5]  Hoffman DR, Boettcher JA, Diersen-Schade DA. Prostaglandins, Leukot Essent Fatty Acids 2009;81:151-158.
[6]  Freeman MP, Hibbeln JR, Wisner KL, et al. Acta Neuropsychiatrica 2006;18(1):21-24.
[7]  Ramakrishnan U, Imhoff-Kunsch B, DiGirolamo AM. Am J Clin Nutr 2009; 89(3):958S-962S.
[8]   Hibbeln JR. J Affect Disord 2002;69(1-3):15-29.
[9]  Stark KD, Beblo S, Murthy M, et al. J Lipid Res 2005;46:516-525.
[10]  Nochera CL, Goossen LH, et al. Nutr Clin Prac 2011;26(4):445-450.
[11]  Denomme J, Stark KD, Holub BJ. J Nutr 2005;135:206-211.
[12]  Davis BC, Kris-Etherton PM. Am J Clin Nutr, 2003;78:640S-646S.
[13]  Francois CA, Connor SL, et al. Am J Clin Nutr, 2003;77(1):226-233.
[14]  Fats and fatty acids in human nutrition: Report of an expert consultation. FAO Food Nutr Pap 2010;91:1-166.
[15]  Hibbeln JR, David JM. Prostaglandins,Leukot & Essent Fatty Acids 2009;81(2-3):179-186.
[16]  Koletzko B, Cetin I, Thomas BJ. Br J Nutr, 2007;1-5.
[17]  Simopoulos AP, Leaf A, Salem N Jr. Prostaglandins, Leukot Essent Fatty Acids 2000;63(3):119-121.