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Omega-3 Optimises Pregnancy Outcomes

During pre-natal care, it is essential to focus on increasing the intake of omega-3 fatty acids. Why? Because they are not make within the body so we either need to eat omega 3 containing foods or supplement them.

During pregnancy tissue stores tend to decline as they are used for the developing foetus so it is important we improve our levels well before trying to conceive.

What are omega 3 fatty acids?

Omega-3 fatty acids are long-chain, polyunsaturated essential fatty acids (EFAs) that cannot be synthesised by the body and therefore must be consumed in our diets.

Other essential fatty acids include omega-6, alpha-linolenic acid (ALA) and linoleic acid (LA), and together they are responsible for many important physiologic functions in the body including oxygen transport, energy storage, cell membrane function, regulation of inflammation, and cell proliferation.

As humans we are able to synthesise saturated and monounsaturated fatty acids HOWEVER we are unable to make omega 3 and omega 6 fatty acids!

Eicosapentoaenoic acid (EPA) and deocosahexaenoic acid (DHA), fatty acids within omega-3s and are key to understanding omega-3’s benefits.

They are precursors of prostaglandins, thromboxanes and leukrotrienes, key players in our inflammatory pathways and therefore have a myriad of anti-inflammatory health benefits.

A diet that has an omega-3 to omega-6 ratio of 1:3 or lower has anti-inflammatory and immune-enhancing benefits. However, todays Western diet more commonly has a ratio of 15:1, 20:1 or higher, which is an inflammatory and immunosuppressive way of eating.

As we know now, inflammation is the root cause of many, if not all modern diseases, and therefore how this ratio looks in your life is extremely important!

Why are omega 3’s so important when looking at falling pregnant?

In pre-conception care, omega-3 fatty acid supplementation reduces the risk of:

  • Preterm birth < 37 weeks
  • Early preterm birth < 34 weeks
  • Low birth weight babies (LBW)
  • Perinatal death*
  • Neonatal care admissions*
  • Low birthweight babies (LBW)
  • Pre-eclampsia and hypertension
  • Peri-natal depression

Additionally, omega-3 fatty acid supplementation improves fetal brain and retina development, reduces the risk of cerebral palsy, and reduces the risk of post-partum depression (now commonly known as post-natal depletion) in the mother.

(The theories behind the studies on birth outcomes were originally observed by the high birth weight babies and long gestation time in cultures that typically have a high consumption of fish)

Other benefits

EPA and DHA which have been shown to influence the constriction of blood vessels, hence the benefits in reducing the risk of high blood pressure and pre-eclampsia during pregnancy.

It is postulated that this same mechanism is why supplementation may delay labour and thus potentially increase the length of pregnancy and increase birth weight, by preventing the production of prostaglandins that encourage the cervix to ‘ripen’.

Therefore, when working with clients who are looking to fall pregnant, making dietary changes and inclusions as well as supplementing with a high-quality, ethically-sourced, clean fish oil supplement is paramount.

What foods are high in omega-3s?

The best source of omega-3 fatty acids are:

  • Oily fish eg salmon
  • Krill oil

The best vegetarian options are:

  • Algae
  • Flaxseed and flaxseed oil (also known as linseeds)
  • Chia seeds
  • Walnuts

They are your highest sources with the optimal omega-3 to omega-6 fatty acid ratio. There are many other foods that have contain a high amount of omega-3s, such as hemp seeds, pastured eggs, and edamame, however because their content of omega-6 levels outweigh the levels of omega-3, I recommended focusing primarily on the first three sources I listed when focusing on your omega-3 intake.

Fish derived Omega 3 is the optimal source

It important to note here that it is a simpler pathway for the body to use fish oil derived EPA and DHA, than it is compared to all vegetarian sources. If you have a look at the diagram below, you’ll see that your vegetarian sources start as alpha-linolenic acid (ALA) and must go through multiple steps that rely on other co-factors, nutrients, and functioning enzymes, before reaching EPA and DHA. It is more difficult for your body to create EPA and DHA out of ALA, but it is not impossible!

How much do I take?

We are looking specifically at the levels of EPA and DHA here. If you cannot see these listed on your supplement, I suggest looking for a better quality one that has EPA/DHA amounts specifically listed.

I like to see levels of EPA around 300 – 500mg/1g, and DHA around 200mg/1g of fish oil.

1 capsule usually equates to about 1g, so each capsule should contain this. Depending on the needs of the individual, anywhere form 2 – 4 capsules daily is what I would prescribe for pre-conception and pregnancy care.

What about quality?

This is such an important component of supplementation, especially regarding any supplementation that involves animal products. The cheapest fish oil at your local chemist, that is about to expire in the bargain bin, that sits out all day in the sun is not going to be particularly anti-inflammatory nor health-promoting! Creating a child is not the time to go hunting for bargains – I really encourage you here to seek the best quality omega-3 supplementation, most of which are practitioner only and need to be prescribed to you for this reason.

Fish are an important source of omega-3 fatty acids, however many types of fish are contaminated with methyl mercury, pesticides or polychlorinated biphenyls (PCBs), harmful substances for the mother and for foetal development.

This is reason I use only high-quality, ultra-purified and distilled, pharmaceutical grade, highly stable concentrated omega-3 fatty acid supplements that have been tested for all major contaminants. Additionally, I encourage my patients to only eat low-mercury, preferably wild-caught, seafood species.

*Preliminary research

If you want to speak with one of our qualified practitioners about your preconception needs or have a question get in touch with us!


Jaclyn Cave, BHSc Nat, BComm Soc

Jaclyn is a qualified naturopath with a focus on anxiety, hormones, acne and stress.

Learn more about Jaclyn here

Book a session with Jaclyn here

To learn more about Omega-3, pregnancy or for speaking enquiries on this topic get in touch at

References Buck G, Tee P, Fitzgerald F, Vena J, Weiner J, Swanson M, Msall M. (2003). Maternal fish consumption and infant birth size and gestation: New York State angler cohort study. Environmental Health. 2:7–16.

Borja-Hart L, Marino J. (2010) Role of omega-3 fatty acids for prevention or treatment of perinatal depression. Pharmacotherapy. 30:210–216.

Cochrane Database of Systematic Reviews. (2018). Omega-3 fatty acid addition during pregnancy.

Coletta J, Bell S, Roman A. (2010). Omega-3 Fatty Acids and Pregnancy. Rev Obstet Gynecol, 3(4), 163-171.

Makrides M, Duley L, Olsen SF. (2006). Marine oil, and other prostaglandin precursor, supplementation for pregnancy uncomplicated by pre-eclampsia or intrauterine growth restriction. Cochrane Database of Systematic Reviews. Issue 3, Art. No.: CD003402.

Nutrition in pregnancy: Scientific Advisory Committee Opinion Paper 18. London, Royal College of Obstetricians and Gynaecologists. 2010.

Ramakrishnan U, Stein AD, Parra-Cabrera S, Wang M, Imhoff-Kunsch B, Juárez-Márquez S, et al. (2010) Effects of docosahexaenoic acid supplementation during pregnancy on gestational age and size at birth: randomized, double-blind, placebo-controlled trial in Mexico. Food and Nutrition Bulletin. 31:S108–S116.

Swanson D, Block R, Mousa S. (2012). Omega-3 Fatty Acids EPA and DHA: Health benefits throughout life. Advances in Nutrition, Volume 3, Issue 1, 1-7.