Fish Oils in Pregnancy

Fish Oils in Pregnancy

Omega 3 fatty acids are extremely important for having a healthy pregnancy. Omega 3s are a type of polyunsaturated fatty acid that are considered essential, and are often referred to as “essential fatty acids” or EFAs.

Types of Omega 3s
There are three main types of Omega 3 fatty acids. Your body can use all three of these Omega 3s to help perform different functions.
• Eicosapentaenoic acid (EPA): EPA is found primarily in fish and fish oil.
• Docosahexanoic Acid (DHA): DHA is especially important to your body, and is also found primarily in fish.
• Alpha-Linolenic Acid (ALA): ALA is found mostly in seeds, vegetable oils, and leafy green vegetables. It is converted into EPA and then into DHA in your body.

Benefits of Omega 3s During Pregnancy
Omega-3s are critical for your baby’s growth and development, playing a crucial role in brain and eye development, since 70% of brain cell development takes place during gestation and is passed from mother to fetus via the placenta. DHA is especially important during pregnancy and lactation because it is the major omega 3 in the central nervous system and retina (O’Brien 1964, Anderson 1975). Supplementation with fish oil during pregnancy results in improved DHA status in infants at birth, thus, your DHA status plays a role in your baby’s DHA status. Birth outcomes seem to be improved in mothers with higher DHA status, with longer gestation and reduced risk of preterm birth (Jacobson 2008, Olsen 2000), improved birth weight (Olsen 1990), and the prevention of neonatal brain injury (Suganuma 2010)

A number of studies link higher maternal DHA status or intake to more mature or favorable behaviors in infants and children, such as:
➢ Accelerated attentional functions (Colombo 1991, Colombo 2004, Willatts 2003)
➢ More mature sleep behavior in newborns (Cheruku 2002)
➢ Higher problem solving (Judge 2007a, 2007b)
➢ Higher visual acuity (Jacobson 2008, Innis 2001, Judge 2007a, Judge 2007b, Williams 2001)
➢ Better discrimination of native from foreign sounds (Innis 2001)
➢ Improved immune system (Prescott 2007, Denburg 2005)
➢ Improved cognitive function in childhood (Oken 2008, Hibbeln 2007)
➢ Better hand-eye coordination at 1 year of age (Dunstan 2008)
➢ Lower blood pressure at 6 years of age (Forsyth 2003)
➢ Improved motor function at 7 years of age (Bakker 2009)

Omega 3s are also necessary for your own health and wellbeing during pregnancy. Women with higher levels of DHA have been shown to be less likely to develop postpartum depression (Hibbeln 2002, Sontrop 2006, Freeman 2006).

Recommended Dosage of Omega 3s
The position of the American Dietetic Association and Dietitians of Canada is that adults should consume a combined intake of 500 mg per day of DHA and EPA, based on an intake of 2000 kcal per day (Kris-Etherton 2007). Specific recommendations for DHA intakes during pregnancy for North Americans are limited to those made by the International Society for the Study of Fatty Acids and Lipids working group, which recommend a minimum of 300 mg per day (Simopoulos 1999) and the Institute of Medicine, which recommends 200-300 mg per day (Nesheim 2007).

Current Consumption of Omega 3s
Pregnant women are reducing their intake of DHA in North America, largely due to the concern expressed regarding the heavy metal toxicity of fish. This is reflected in lower breast-milk DHA concentrations. For example, in US women, milk DHA concentration is 0.2% of total fatty acids, whereas in some Chinese women it is 2.8% of fatty acids (Carlson 2009). In fact, the mean DHA intake in Canadian women is 82 mg per day with 90% of women consuming less than the recommended 300 mg per day during pregnancy (Denomme 2005).

Maternal DHA Status Declines Throughout Pregnancy
Overall maternal essential fatty acid status declines steadily during pregnancy. For example, a study of 110 pregnant women found a temporary increase in DHA status until 20 weeks, but then a steady decline thereafter. This pattern was associated with a progressive DHA deficiency in maternal blood throughout pregnancy and resulted in a sub-optimal neonatal DHA status (Al 1995).

When To Take Omega 3s
Expectant mothers should begin to include essential fatty acids in their diets in early pregnancy to ensure that DHA is passed on to the baby’s tissues during the gestational period. The susceptible window during which dietary DHA may be needed to optimize brain development is a relatively long one and extends from mid-pregnancy (Helland 2003) into the first year of life (Jensen 2005). The most rapid rates of brain DHA accumulation in fetal brain occur during the third trimester and the first year of life (Carlson 2009). Because we are not sure whether postnatal supplementation can correct fully for prenatal deficiency, it also seems appropriate to assure an adequate maternal intake throughout pregnancy and lactation. Two strategies could make more DHA available for brain development: maternal diet could include more fish and, where that is not possible, a supplement could be provided.

Good Omega 3 Sources
Fish is definitely the best source of EFAs and it has the added bonus of being an excellent source of protein. However, given that fish can contain high levels of mercury, certain recommendations regarding fish consumption during pregnancy have been fairly well established, including:
1. Do not eat shark, swordfish, king mackerel, or tilefish;
2. Twelve ounces or less per week of fish and shellfish lower in mercury, such as shrimp, canned light tuna, salmon, pollock, and catfish is considered safe;
3. Limit albacore (“white”) tuna to 6 oz or less per week since this type of tuna contains more mercury than canned light tuna.

Fish oil supplements are available but you must check to make sure that your supplements are not made from fish livers (ie. cod liver oil). The liver can contain high amounts of vitamin A, which has been linked to birth defects. Omega-3 supplements not derived from fish livers but rather from the body of the fish are less likely to contain this type of vitamin A.

Food companies have also responded to all of the scientific and consumer interest in essential fatty acids by adding them into commonly consumed foods. For example:
➢ each 100 gram serving of Danino yogurt from Danone contains 40 mg of DHA and 25 mg of EPA;
➢ each Omega Pro egg provides 125 mg of DHA;
➢ each 50 mL serving of Break-Free Omega-3 liquid eggs provides 125 mg of DHA and 125 mg of EPA;
➢ each 250 mL of Nielson Dairy Oh 1%, 2%, and chocolate milks provide 10 mg of DHA and the homogenized milk provides 20 mg DHA.

The plant-derived omega 3 fatty acid (ALA) acid can be found in such foods as flax, canola oil, and walnuts. Below, I have listed the percentage of ALA by weight of some plant foods:
– Flaxseed: 22%
– Flax oil: 50.8%
– Hemp: very trivial
– Canola oil: 9.3% HOWEVER, these foods have NO EPA and DHA
– Soy oil: 7.0%
– Nuts: 0.2 – 0.4%
– Walnuts: 6.8%

Some of these foods are quite high in ALA. In fact, about 2000 mg of ALA is typically consumed daily in North America. However, DHA and EPA are NOT present in the plant sources of ALA – instead, a metabolic conversion has to occur to convert ALA into DHA and EPA. And what most people don’t realize is that humans have a very poor ability to convert these plants sources of ALA into DHA and EPA. The exact conversion rate of ALA to DHA in humans is controversial, but just to give you an idea of how inefficient this conversion is, it ranges from < 0.2% (Pawlosky 2001, 2003) to 3.8% (Emken 1994). Therefore, you have to eat a lot of flax or walnuts to get a good dosage of DHA and EPA.

Al M, Van Houwelingen AC, Kester A, Hasaart Tom, De Jong A, Hornstra G. (1995). Maternal essential fatty acid patterns during normal pregnancy and their relationship to the neonatal essential fatty acid status. British Journal of Nutrition; 74:55-68

Anderson RE, Maude MB, Zimmerman W. (1975). Lipids of ocular tissues. X. Lipid composition of subcellular fractions of bovine retina. Vision Res;15:1087–90.

Bakker EC, Hornstra G, Blanco CE, Vles JSH. (2009). Relationship between long-chain polyunsaturated fatty acids at birth and motor function at 7 years of age. Eur J Clin Nutr; 63(4):499-504.

Cheatham CL, Colombo J, Carlson SE. (2006). n–3 Fatty acids and cognitive and visual acuity development: methodologic and conceptual considerations. Am J Clin Nutr;83(suppl):1458S–66S.

Cheruku SR, Montgomery-Downs HE, Farkas SL, Thoman EB, Lammi-Keefe CJ. (2002). Higher maternal plasma docosahexaenoic acid during pregnancy is associated with more mature neonatal sleep-state patterning. Am J Clin Nutr;76:608–13.

Colombo J, Kannass KN, Shaddy DJ, Kundurthi S, Maikranz JM, Carlson SE. (2004). Maternal DHA and the development of attention in infancy and toddlerhood. Child Dev;75:1254–67. e

Colombo J, Mitchell D, Coldren JT, Freeseman LJ. (1991). Individual differences in infant visual attention: are short lookers faster processors or feature processors? Child Dev;62:1247–57.

Denburg JA, Hatfield HM, Cyr MM, et al. (2005). Fish oil supplementation in pregnancy modifies neonatal progenitors at birth in infants at risk of atopy. Pediatr Res;57:276–81.

Denomme J, Stark KD, Holub BJ. (2005). Directly Quantitated Dietary (n-3) Fatty Acid Intakes of Pregnant Canadian Women Are Lower than Current Dietary Recommendations. J. Nutr. 135:206-211.

Dunstan JA, Simmer K, Dixon G, Prescott SL. (2008). Cognitive assessment of children at age 2(1/2) years after maternal fish oil supplementation in pregnancy: a randomized control trial. Arch Dis Child Fetal Neonatal Ed;93:F45–50.

Emken, E. A., Adlof, R. O. & Gulley, R. M. (1994). Dietary linoleic acid influences desaturation and acylation of deuterium-labeled linoleic and linolenic acids in young adult males. Biochim. Biophys. Acta 1213:277-288

Forsyth JS, Willatts P, Agostoni C, Bissenden J, Casaer P, Boehm G. (2003). Long chain polyunsaturated fatty acid supplementation in infant formula and blood pressure in later childhood: follow up of a randomized controlled trial. BMJ;326:953.

Freeman MP. (2006). Omega-3 fatty acids and perinatal depression: a review of the literature and recommendations for future research. Prostaglandins Leukot Essent Fatty Acids;75:291–7.

Harper MA for the NICHD Maternal Fetal Medicine Units Network. (2008). Randomized controlled trial of omega-3 fatty acid supplementation for recurrent preterm birth prevention. Program and Abstracts of the 8th Meeting of the International Society for the Study of Fatty Acids and Lipids; 57 (abstr). Available from:, CS1.6 (cited 10 December 2008).

Helland IB, Saugstad OD, Smith L, et al. (2001). Similar effects on infants of n–3 and n26 fatty acids supplementation to pregnant and lactating women. Pediatrics;108:e82.

Hibbeln JR, Davis JM, Steer C, et al. (2007). Maternal seafood consumption in pregnancy and neurodevelopmental outcomes in childhood (ALSPAC study): an observational cohort study. Lancet;369:578–85.

Hibbeln JR. (2002). Seafood consumption, the DHA content of mothers’ milk and prevalence rates of postpartum depression: a cross-national ecological analysis. J Affect Disord;69:15–29.

Innis SM, Gilley J, Werker J. (2001). Are human milk long-chain polyunsaturated fatty acids related to visual and neural development in breast-fed infants? J Pediatr;139:532–8.

Jacobson JL, Jacobson SW, Muckle G, Kaplan-Estrin M, Ayotte P, Dewailly E. (2008). Beneficial effects of a polyunsaturated fatty acid on infant development: evidence from the Inuit of arctic Quebec. J Pediatr; 152:356–74.

Judge MP, Harel O, Lammi-Keefe CJ. (2007a). A docosahexaenoic acid- functional food during pregnancy benefits infant visual acuity at four but not six months of age. Lipids;42:117–22.

Judge MP, Harel O, Lammi-Keefe CJ. (2007b). Maternal consumption of a docosahexaneoic acid-containing functional food during pregnancy: benefit for infant performance on problem-solving but not on recognition memory tasks at 9 mo. Am J Clin Nutr;85:1572–7.

Kris-Etherton PM, Innis S. (2007). Position of the American Dietetic Association and Dietitians of Canada: dietary fatty acids. J Am Diet Assoc; 107:1599–611.

Morale SE, Hoffman DR, Castaneda YS, Wheaton DH, Burns RA, Birch EE. (2005). Duration of long-chain polyunsaturated fatty acid availability in the diet and visual acuity. Early Hum Dev;81:197–203.

Nesheim MC, Yaktine AL, eds. (2007). Seafood choices: balancing benefits and risks. Analysis of the balancing of benefits and risks of seafood consumption. Washington, DC:, National Academies Press; 195–216.

Neuringer M, Connor WE, Lin DS, Barstad L, Luck S. (1986). Biochemical and functional effects of prenatal and postnatal omega 3 fatty acid deficiency on retina and brain in rhesus monkeys. Proc Natl Acad Sci U S A; 83:4021–5.

O’Brien JS, Rouser G. (1964). Quantification and fatty acid and fatty aldehyde composition of ethanolamine, choline and serine glycerophosphatides in human cerebral grey and white matter. J Lipid Res;5:329–38.

Oken E, Radesky JS, Wright RO, et al. (2008). Maternal fish intake during pregnancy, blood mercury levels, and child cognition at age 3 years in a US cohort. Am J Epidemiol;167:1171–81.

Olsen SF, Secher NJ, Tabor A, Weber T, Walker JJ, Gluud C. (2000). Randomised clinical trials of fish oil supplementation in high risk pregnancies. Fish Oil Trials in Pregnancy (FOTIP) Team. BJOG;107:382–95.

Pawlosky RJ, Hibbeln JR, Lin Y, Goodson S, Riggs P, Sebring N, Brown GL, Salem N Jr. (2003) Effects of beef- and fish-based diets on the kinetics of n-3 fatty acid metabolism in human subjects. Am. J. Clin. Nutr; 77:565-572

Pawlosky RJ, Hibbeln JR, Novotny JA, Salem N Jr. (2001) Physiological compartmental analysis of alpha-linolenic acid metabolism in adult humans. J. Lipid Res; 42:1257-1265.

Prescott SL, Barden AE, Mori TA, Dunstan JA. (2007). Maternal fish oil supplementation in pregnancy modifies neonatal leukotriene production by cord-blood-derived neutrophils. Clin Sci (Lond);113:409–16.

Reisbick S, Neuringer M, Gohl E, Wald R, Anderson GJ. (1997). Visual attention in infant monkeys: effects of dietary fatty acids and age. Dev Psychol;33:387–95.

Simopoulos AP, Leaf A, Salem N Jr. (1999) Workshop on the essentiality of and recommended dietary intakes for omega-6 and omega-3 fatty acids. J Am Coll Nutr; 18:487-489.

Sontrop J, Campbell MK. (2006). Omega-3 polyunsaturated fatty acids and depression: a review of the evidence and a methodological critique. Prev Med;42:4–13.

Suganuma H, Arai Y, Kitamura Y, Hayashi M, Okumura A, Shimizu T. (2010). Maternal docosahexaenoic acid-enriched diet prevents neonatal brain injury. Neuropathology. Apr 8 (ahead of print).

Williams C, Birch EE, Emmett PM, Northstone K, Avon Longitudinal Study of Pregnancy and Childhood Study Team. (2001). Stereoacuity at age 3.5 y in children born full-term is associated with prenatal and postnatal dietary factors: a report from a population-based cohort study. Am J Clin Nutr;73:316–22.

Willatts P, Forsyth S, Mires G, Ross P. (2003). Maternal DHA status during pregnancy is related to measures of infant look duration and acuity at age 4 months. Society for Research in Child Development Abstracts.

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