By Dr Anita Star
Yes that is right we love fish in pregnancy!
I thought you had to avoid fish in pregnancy I hear many people say. Well there is an element of truth, it is best to avoid a number of fish types due to high mercury content. BUTTTTT and this is a big one – 3 X 150g serves of low mercury fish has enormous benefits for both mum and baby. If anything we need to be encouraging low mercury fish in pregnancy.
Benefits of fish in pregnancy
Research has found regular fish intake in pregnancy has been associated with
- Lower risk of preterm delivery
- Lower risk of allergy in resulting children
- Greater likelihood of Higher cognitive performance in resulting children
- some research even indicates a lower risk of Autism spectrum traits in resulting children
- and perhaps even lower risk of post- natal depression
So make sure you get some low mercury fish as a part of your shopping trolley.
Great low mercury fish options in Australia include:
- Salmon (canned or fresh)
Can I just have a supplement?
Talk to your doctor if you wish to take an omega 3 supplement. At this stage the research seems to be indicating an omega 3 supplement may not be as beneficial as actual fish.
Which fish do I need to avoid?
- Shark and flake – this is often what is in unidentified fish when you buy fish and chips from the corner store, or processed and crumbed fish portions. So be careful and always ask about the type of fish used when eating out.
- Orange roughy ( also called sea perch)
- Southern Blufin Tuna
- Lake trout from the geothermal regions of New Zealand (NZ) and Lake Rotomahana trout
- NZ Dogfsh
- NZ Cardinal Fish
- Recreational fishers should look for current local advisory information about mercury contamination from past mining or other industry at their fishing site. Examples of local contamination include Lake trout and Redfin from Lake Eildon in Victoria; and carp, redfin, Murry cod, golden perch from the Lodden river between Laanecoorie Reservoir to Bridgewater in Victoria- pollution from historical gold mining. Other sites across Australia and New Zealand can also be affected.
Also be aware of the following tips
When living or traveling in New Zealand avoid fish from lakes or rivers supplied from geothermal water, as mercury is commonly found in volcanic emissions and can build up in fish swimming in these waters.
Avoid buying fish caught in heavily polluted Asian waterways. There is quite a bit of this in the Australian market.
We recommend buying Australian and New Zealand caught or grown fish, as mercury content of Australian ocean fish other than the large predatory fish is mostly quite low.
If you are travelling outside of Australia we recommend seeking the local advice on mercury content of fish. The names of fish can change in each region. Also different fishing grounds in other regions of the world have different levels of mercury, which will impact on the types of fish which are safe or which you need to avoid in that region.
Raw or smoked fish should also be avoided for potential unsafe bacterial contamination.
If you accidentally eat one of these higher mercury fish when pregnant, simply avoid all other fish for 2 weeks.
If you have eaten a lot of high mercury fish pre-pregnancy discuss it with your doctor.
Did you know?
Avoiding fish types high in mercury is also important for kids up to 6 years of age. Again fish consumption once your child has started solids if extremely healthy for their ongoing brain development and mental health, but knowledge in selecting options low in Mercury is important.
We need to clean up our oceans, rivers and lakes
Mercury is a heavy metal toxin mainly caused by various industries including the mining industry and coal powered power plants. It stays in our environment for a very long time and fish can absorb it. Longer living fish, large predatory fish (that eat smaller fish with smaller amounts of mercury, which then build up in the larger fishes system), and fish that live in heavily polluted water ways, have the highest mercury levels. Mercury is toxic for the environment and toxic for us. I think greater effort needs to made to clean up industrial pollutants. As mercury lasts so long in the environment, pollution created many years ago, before perhaps our current environmental standards, are still impacting on the environment and us.
Take home message:
We are extremely fortunate in Australia and New Zealand to have some great tasting, low mercury fish options. Please enjoy up to 3 X 150mg serves of low mercury fish per week to get the health benefits of fish during pregnancy.
Best, Karen P., et al. “Omega-3 long-chain PUFA intake during pregnancy and allergic disease outcomes in the offspring: a systematic review and meta-analysis of observational studies and randomized controlled trials.” The American journal of clinical nutrition 103.1 (2016): 128-143.
Brantsæter, Anne Lise, et al. “Maternal intake of seafood and supplementary long chain n-3 poly-unsaturated fatty acids and preterm delivery.” BMC pregnancy and childbirth 17.1 (2017): 41.
Julvez, Jordi, et al. “Maternal consumption of seafood in pregnancy and child neuropsychological development: a longitudinal study based on a population with high consumption levels.” American journal of epidemiology 183.3 (2016): 169-182.
Markhus, Maria Wik, et al. “Low omega-3 index in pregnancy is a possible biological risk factor for postpartum depression.” PloS one 8.7 (2013): e67617.
Lin, Pao-Yen, et al. “Polyunsaturated Fatty Acids in Perinatal Depression: A Systematic Review and Meta-analysis.” Biological Psychiatry (2017).
NSW Department of Primary Industry- Food Authority. Mercury and Fish (Website accessed April 2017)
Starling, Phoebe, et al. “Fish intake during pregnancy and foetal neurodevelopment—A systematic review of the evidence.” Nutrients 7.3 (2015): 2001-2014.
Strain, J. J., et al. “Prenatal exposure to methyl mercury from fish consumption and polyunsaturated fatty acids: associations with child development at 20 mo of age in an observational study in the Republic of Seychelles.” The American journal of clinical nutrition 101.3 (2015): 530-537.
Department of Health and Human Services, State Govt. of Victoria. Mercury in Fish (website accessed May 2017)