Omega 3 and preterm birth
There is always a delay between the publication of research and the incorporation of the outcomes into guidelines, and from there, a further delay between updated guidelines and a change in practice. Sometimes there is ongoing debate about what the research means and if we should (and if so, how do we) incorporate the outcomes into clinical practice. This is the case with the research identifying a link between low levels of Omega 3 and preterm birth
A Cochrane systematic review of 70 randomised controlled trials of almost 20,000 women with mainly singleton pregnancies indicated that omega-3 supplementation from early-mid pregnancy until birth reduces the risk of early preterm birth by 42% (from 46 per 1000 to 27 per 1000 births) and preterm birth by 11% (from 134 per 1000 to 119 per 1000 births)
In the overall analysis, preterm birth < 37 weeks and early preterm birth < 34 weeks were reduced in women receiving omega-3 long-chain polyunsaturated fatty acids (LCPUFA) compared with no omega-3. There was a possibly reduced risk of perinatal death and of neonatal care admission, a reduced risk of low birth weight babies; and possibly a small increased risk of large for gestational age babies with omega-3 LCPUFA
Other researchers caution that the data is inconclusive, and more research is needed
Some of this research was conducted prior to Omega 3 being added to (some, not all) antenatal supplements. For example, Blackmore’s Pregnancy Gold has 250 mg of Omega 3’s but their Multivitamin for Women does not. Elevit Preconception and Pregnancy does not, Elevit DHA (docosahexaenoic acid) and Choline (to be taken in addition to the Preconception and Pregnancy supplement) and Elevit Breastfeeding both contain 200 mg of DHA. A list of supplements with and without Omega 3’s is available here
The Australian Pregnancy Care Guidelines include a recommendation (number 10) for supplementation in those whose levels are low
Universal supplementation is not recommended as supplementation of those with high levels of Omega 3 is associated with an increase in preterm birth
Testing for Omega 3 is not Medicare funded in Australia and costs ~ $265 (Source: SNP, a Sonic pathology provider, March 2023). It should be offered before 20 weeks, preferably in the first trimester, and the interpretation of results and actions to follow are outlined here.
Long story short, if there are low levels of omega-3 (Less than 3.7% of total fatty acids), the suggested dose is 800 mg DHA and 100 mg EPA (eicosapentaenoic acid) per day until 37 weeks, starting by 20 weeks. If moderate levels (3.7- 4.3%), no change is required (keep doing what is being done re diet +/- supplements) and if the levels are sufficient (above 4.3%), supplements are not required, but if taken should not exceed 250 mg of DHA + EPA a day
South Australia (SA) has commenced a funded program of testing in early pregnancy for Omega 3 levels with a view to supplementing those whose levels are low. Sites outside SA vary in their approach - some are testing and supplementing, others are awaiting the results of the SA intervention. At this time (May 2023) there is not a standard way to represent the findings across Australia, so unless you are in South Australia where they have standards in place, testing may leave you with a result you can not interpret. For more information, Prof Craig Pennell, Maternofetal Medicine specialist from Newcastle, Australia, speaks for 7 minutes at the 22:08 mark here
The MJA published “The role of omega‐3 polyunsaturated fatty acids in the prevention of preterm birth” on the 3rd of June 2024 and the conclusion is: Measurement of omega‐3 levels is required before the initiation of omega‐3 supplementation to reduce the risk of preterm birth in pregnant women with low omega‐3 status and to minimise potential harm in those who are omega‐3 replete. Affordable and accessible testing and consistent approaches to reporting are required to implement nationwide programs to reduce preterm births.
Natural sources of Omega 3 include
Fish and other seafood (especially cold-water fatty fish, such as salmon, mackerel, tuna, herring, and sardines)
Nuts and seeds (such as flaxseed, chia seeds, and walnuts)
Plant oils (such as flaxseed oil, soybean oil, and canola oil)
There are supplements made from algal oil suitable for vegetarians and vegans
Like folic acid, humans absorb Omega 3s differently, making it hard to be confident about serum levels from dietary sources, however deficiency is unlikely if fish is eaten twice weekly